3D printing device and method

ABSTRACT

A 3D printing device (100), comprising a melt extrusion module (102), a printing module (103), and a platform module (104). The melt extrusion module (102) comprises a processing chamber (121) consisting of a feed inlet (124) and a discharge outlet (125), as well as an extrusion means (122) and a heating means (123) disposed at the processing chamber; the melt extrusion module (102) is configured to receive an initial material from the feed inlet (124) of the processing chamber (121), and heat and extrude the initial material to convert the initial material into a molten body, which is extruded out of the discharge outlet (125) of the processing chamber (121). The printing module (103) is communicated with the discharge outlet (125) of the processing chamber (121) and is provided with a nozzle (131); the printing module (103) is configured to receive the molten body extruded from the discharge outlet (125) of the processing chamber (121) and guide the molten body to be extruded out of the nozzle (131). The platform module (104) is configured to receive the molten body extruded from the nozzle (131).

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national stage application under 35 U.S.C. § 371of International Application No. PCT/CN2018/086489, filedinternationally on May 11, 2018, which claims priority benefit fromInternational Application No. PCT/CN2018/071965, filed internationallyon Jan. 9, 2018, and CN201710347098.1, filed May 16, 2017, the entiredisclosure of each of which is incorporated herein by reference in itsentirety.

FIELD OF THE PRESENT APPLICATION

The present application relates to a device and a method related to anadditive manufacturing technology, and in particular, to a 3D printingdevice and a 3D printing method.

BACKGROUND OF THE PRESENT APPLICATION

3D printing is a rapid prototyping technology. Based on a digital model,3D printing can be used to manufacture products by using bondablematerials, such as metal or plastics, in a layer-by-layer printingmanner. With the rapid development of related technologies, 3D printingis widely applied in jewelry, engineering, automobile, dental,aerospace, and medical industries.

Currently, fused deposition modeling (FDM) is currently a common 3Dprinting technology. Usually, a 3D printing device using this technologyheats a filament made of a material, such as ABS or PLA, to reach atemperature slightly higher than a melting temperature, and extrudes amelt in a layer-by-layer manner under the control of a computer or acontroller, to stack and build up a required product. Usually, such anexisting 3D printing device poses a limitation on the texture of aninitial material before melting. For example, usually a material to befed to a 3D printing device based on the fused deposition modelingtechnology must be linear or filamentous, and this obviously restrictsthe application scope of such a 3D printing device. For example, duringapplication of the fused deposition modeling technology in 3D printingof pharmaceuticals, if an drug excipient or an active ingredient of adrug is conveyed in a filamentous form to a printing device, arequirement on the drug loading rate of an initial material needed for3D printing of the drug cannot be satisfied due to a limitation in theshape of a filamentous material.

Sometimes a powdered raw material is used for 3D printing ofpharmaceuticals in practical application. However, because a 3D printingdevice in industrial application uses a three-dimensional powder-liquidprinting technology with powder stratification and adhesive bonding,there may be a problem of powder collection and reclamation caused bystratified spraying of powder. In addition, there are few pharmaceuticaldosage forms to which this technology is applicable during 3D printing,and it is difficult for pharmaceutical products printed using thistechnology to satisfy requirements such as sustained release andzero-order release.

During product manufacturing, especially during manufacturing of apharmaceutical product, it is desirable to exactly control an amount ofmaterial that is dispensed by a nozzle. A major problem of aconventional apparatus for additive manufacturing is unintended leakageof the material through the nozzle, which can cause more than a desiredamount of material to be dispensed. The problem becomes more complexwhen two or more nozzles are used. These nozzles may dispense differentmaterials, which requires alternate switching-on or switching-off. Forexample, if a first material is leaking from a first nozzle when asecond nozzle is dispensing a second material, a manufacturing defect ora material waste arises. As the devices and systems according to thepresent invention can handle a range of pharmaceutical materials withhigh accuracy and high precision of material deposition, these devicesand systems are very suitable for fabricating pharmaceutical dosageforms with complex geometry and composition. In addition, the devices,systems, and methods according to the present invention are alsoconducive to personalized medicine, including personalized doses and/orpersonalized release profiles. Personalized medicine refers tostratification of patients based on biomarkers, to help with therapeuticdecision-making and personalized dosage form design. Personalizedpharmaceutical dosage forms allow for tailoring an amount of drug to bedelivered, including release profiles, based on a patient's mass andmetabolism. Pharmaceutical dosage forms manufactured using the devicesaccording to the present invention can ensure accurate dosing forgrowing children, and permit personalized dosing of highly potent drugs.Personalized pharmaceutical dosage forms can also be used to combine allof patients' medications into a single daily dose, to improve patients'adherence to medication and treatment compliance. It is much easier tomodify a digital design than modifying a physical device. Furthermore,automated small-scale three-dimensional printing may have a negligibleoperating cost. Therefore, the additive manufacturing apparatusesaccording to the present invention can make multiple smallindividualized batches become economically feasible and achievepersonalized dosage forms designed to improve adherence.

Compared with conventional “batch production” of pharmaceuticals,“continuous production” of pharmaceuticals uses a process analysistechnology (PAT) (for example, a near-infrared technology) to providequality information continuously in real time, so that a final productcan be directly launched onto a market. Such a production processgreatly improves usage efficiency of manufacturing equipment, and moreimportantly, improves quality of pharmaceuticals. In addition, asquality inspection is performed continuously during a productionprocess, scraps in batches can be effectively avoided, and storage andtransportation costs of an intermediate product are also saved as anintermediate process is spared. It can be predicted that, in theforeseeable future, the “continuous production” manner will probablybecome a mainstream trend of pharmaceutical production, just like 3Dprinting of pharmaceuticals. However, “continuous production” requiresfully-sealed vacuum feeding to avoid cross contamination, and allinspection work needs to be done during the production process.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide a 3D printing devicecapable of resolving the foregoing defects and deficiencies.

In one aspect of the present invention, a 3D printing device isprovided, including a first melt extrusion module, a first printingmodule, and a platform module. The first melt extrusion module includesa processing chamber having a feed inlet and a discharge outlet, and anextrusion apparatus and a heating apparatus that are disposed in theprocessing chamber. The first melt extrusion module is configured toreceive a first initial material through the feed inlet of theprocessing chamber and heat and extrude the first initial material, sothat the first initial material is converted into a first melt and thefirst melt is extruded from the discharge outlet of the processingchamber. The first printing module is connected to the discharge outletof the processing chamber, and has a first nozzle. The first printingmodule is configured to receive the first melt extruded from thedischarge outlet of the processing chamber and guide the first melt tobe extruded through the first nozzle. The platform module is configuredto receive the first melt extruded through the first nozzle.

In some embodiments of the present invention, the first printing moduleis configured to perform melting and pressurization. The first printingmodule includes a feed channel connected to a printing head, where theprinting head includes a nozzle, and the nozzle includes a tapered innersurface and an extrusion port configured to dispense a material; apressure sensor, where the pressure sensor is configured to measure thepressure of the material within the nozzle or within the feed channelproximal to the nozzle; and a control switch, where the control switchincludes a sealing needle operable between an open position and a closedposition, the sealing needle extends through a portion of the feedchannel and includes a tapered end, and the tapered end of the sealingneedle engages with the tapered inner surface of the nozzle, so as toinhibit the material from flowing through the nozzle when the sealingneedle is in the closed position.

In one aspect of the present invention, the 3D printing device isconfigured to deposit a material or manufacture a product (for example,a pharmaceutical dosage form) through additive manufacturing byprecisely controlling the pressure in the nozzle or the pressure in thefeed channel proximal to the nozzle. When the sealing needle is in theclosed position, the control switch equipped with the sealing needleinhibits the material from flowing through the nozzle. The nozzleincludes a tapered inner surface, and the sealing needle includes atapered end, where the tapered end engages with the tapered innersurface of the nozzle to inhibit the material from leaking. The sealingneedle is preferably sharp and thin, and free of protrusions, as anyprotrusion could probably push the material out of the nozzle when thesealing needle is in the closed position. Preferably, the pressure ofthe material remains approximately constant in the device. The pressureof the material can be controlled by monitoring the pressure and using afeedback system to pressurize the material. In this way, once thesealing needle is positioned in the open position, the material can beimmediately extruded at a constant rate without a need to ramp up thepressure. This can further implement exact material dispensing, to allowfor precise and accurate manufacturing of a drug dose unit, for example,a pharmaceutical tablet.

In some embodiments of the present invention, any portion of the sealingneedle that contacts the material is free of protrusions.

In some embodiments of the present invention, the tapered end of thesealing needle includes a pointed tip. In some embodiments, the taperedend of the sealing needle is frustoconical. In some embodiments, thetapered inner surface of the nozzle has a first taper angle, and thetapered end of the sealing needle has a second taper angle, where thesecond taper angle is equal to or less than the first taper angle. Insome embodiments, the second taper angle is about 60° or less. In someembodiments, the second taper angle is about 45° or less. In someembodiments, a ratio of the first taper angle to the second taper angleis about 1:1 to 4:1.

In some embodiments of the present invention, the extrusion port has adiameter of about 0.1 mm to 1 mm. In some embodiments, the tapered endhas a largest diameter of about 0.2 mm to about 3.0 mm. In someembodiments, the extrusion port has a diameter, and the tapered end hasa largest diameter, where a ratio of the largest diameter of the taperedend to the diameter of the extrusion port is about 1:0.8 to about 1:0.1.

In some embodiments of the present invention, the control switchincludes an actuator, where the actuator can position the sealing needleat the open position or the closed position. In some embodiments, theactuator is a pneumatic actuator. In some embodiments, the actuator is amechanical actuator.

In some embodiments of the present invention, the sealing needle passesthrough a gasket fixed at a position relative to the nozzle, where thegasket seals the feed channel.

In some embodiments of the present invention, the tapered end of thesealing needle or the tapered inner surface of the nozzle includes aflexible pad or liner.

In some embodiments of the present invention, the material isnon-filamentous. In some embodiments, the material has a viscosity ofabout 100 Pa·s or more when extruded from the device. In someembodiments, the material has a viscosity of about 400 Pa·s or more whenextruded from the device. In some embodiments, the material melts atabout 50° C. to 400° C. In some embodiments, the material is extrudedfrom the nozzle at a temperature of about 50° C. to 400° C. In someembodiments, the material is extruded from the nozzle at a temperatureof about 90° C. to 300° C.

In some embodiments of the present invention, the 3D printing devicefurther includes a first feeding module. The first feeding moduleincludes a hopper, and the hopper has an feed inlet and a dischargeoutlet, and is configured to receive the first initial material throughthe feed inlet of the hopper and discharge the first initial material tothe feed inlet of the processing chamber of the first melt extrusionmodule through the discharge outlet of the hopper.

In some embodiments of the present invention, the 3D printing devicefurther includes a control module. The control module includes acomputerized controller, configured to control the 3D printing devicebased on a status parameter of the 3D printing device.

In some embodiments of the present invention, the 3D printing devicefurther includes a first temperature measurement apparatuscommunicatively connected to the control module. The first temperaturemeasurement apparatus is configured to measure the temperature of thefirst melt in the processing chamber and transmit a first temperaturemeasurement signal to the control module.

In some embodiments of the present invention, the heating apparatus ofthe processing chamber is communicatively connected to the controlmodule, and the control module controls heating power of the heatingapparatus of the processing chamber according to the first temperaturemeasurement signal.

In some embodiments of the present invention, the extrusion apparatus iscommunicatively connected to the control module, and the control modulecontrols extrusion power of the extrusion apparatus according to thefirst temperature measurement signal.

In some embodiments of the present invention, the extrusion apparatusincludes a screw. The screw is disposed in the processing chamber, toextrude the first initial material or the first melt and convey thefirst melt to the discharge outlet of the processing chamber.

In some embodiments of the present invention, the screw extruder is asingle screw extruder, or twin screw extruder, or a combination thereof.

In some embodiments of the present invention, the first melt extrusionmodule includes a melt extrusion discharge control apparatus, and themelt extrusion discharge control apparatus is configured to control thedischarge speed of the first melt at the discharge outlet of theprocessing chamber.

In some embodiments of the present invention, the 3D printing devicefurther includes: a first pressure measurement apparatus, where thefirst pressure measurement apparatus is communicatively connected to thecontrol module, and configured to measure the pressure of the first meltin the first printing module and transmit a first pressure measurementsignal to the control module; and a pressure regulating apparatus, wherethe pressure regulating apparatus is disposed in the first printingmodule, and configured to regulate the pressure of the first melt in thefirst printing module, and the control module is communicativelyconnected to the pressure regulating apparatus, and regulates thepressure of the first melt in the first printing module by using thepressure regulating apparatus according to the first pressuremeasurement signal.

In some embodiments of the present invention, the pressure sensor isconnected to a computer system that controls the first printing modulein response to the pressure reported by the pressure sensor andpressurizes the material to a required pressure. In some embodiments,the pressure of the material is within 0.05 MPa of the requiredpressure. In some embodiments, the first printing module includes apiston and a barrel that is connected to the feed channel, where thepiston is driven to control the pressure of a material in the barrel. Insome embodiments, the piston is driven by a stepper motor.

In some embodiments of the present invention, the 3D printing devicefurther includes: a second temperature measurement apparatus, where thesecond temperature measurement apparatus is communicatively connected tothe control module, and configured to measure the temperature of thefirst melt in the first printing module and transmit a secondtemperature measurement signal to the control module; and a temperatureregulating apparatus, where the temperature regulating apparatus isdisposed in the first printing module, and configured to regulate thetemperature of the first melt in the first printing module, and thecontrol module is communicatively connected to the temperatureregulating apparatus, and regulates the temperature of the first melt inthe first printing module through the temperature regulating apparatusaccording to the second temperature measurement signal. In someembodiments, the second temperature measurement apparatus is connectedto a computer system, and the computer system controls a correspondingtemperature regulating apparatus according to the temperature monitoredby the second temperature measurement apparatus.

The present invention provides a more precise system, configured todeposit a material or manufacture a product (for example, apharmaceutical dosage form) through additive manufacturing by preciselycontrolling the pressure of the nozzle or the pressure of the feedchannel proximal to the nozzle. When the sealing needle is in the closedposition, the control switch equipped with the sealing needle inhibitsthe material from flowing through the nozzle. The nozzle includes atapered inner surface, and the sealing needle includes a tapered end,where the tapered end engages with the tapered inner surface of thenozzle to inhibit the material from leaking. The sealing needle ispreferably sharp and thin, and free of protrusions, as any protrusioncould probably push the material out of the nozzle when the sealingneedle is in the closed position. Preferably, the pressure of thematerial remains approximately constant in the device. The pressure ofthe material can be controlled by monitoring the pressure and using afeedback system to pressurize the material. In this way, once thesealing needle is positioned in the open position, the material can beimmediately extruded at a constant rate without a need to ramp up thepressure. This can further implement exact material dispensing, to allowfor precise and accurate manufacturing of a drug dose unit, for example,a pharmaceutical tablet.

In some embodiments of the present invention, the first feeding modulefurther includes a hopper discharge control apparatus, and the hopperdischarge control apparatus is configured to control the discharge speedof the first initial material at the discharge outlet of the hopper.

In some embodiments of the present invention, the hopper dischargecontrol apparatus is a screw, and the screw is disposed in the hopperand controls the discharge speed of the first initial material at thedischarge outlet of the hopper by changing the rotational speed of thescrew.

In some embodiments of the present invention, the 3D printing devicefurther includes: a second feeding module, configured to receive asecond initial material through a feed inlet of a hopper of the secondfeeding module and discharge the second initial material through adischarge outlet of the hopper of the second feeding module.

In some embodiments of the present invention, the 3D printing devicefurther includes: a first composition measurement apparatus, where thefirst composition measurement apparatus is communicatively connected tothe control module, and configured to measure a composition of the firstmelt at any position of the 3D printing device and transmit a firstcomposition measurement signal to the control module; and the hopperdischarge control apparatus of the first feeding module and a hopperdischarge control apparatus of the second feeding module arecommunicatively connected to the control module, so that the controlmodule controls, according to the first composition measurement signal,the discharge speed of the first initial material at the dischargeoutlet of the hopper of the first feeding module and the discharge speedof the second initial material at the discharge outlet of the hopper ofthe second feeding module respectively through the hopper dischargecontrol apparatus of the first feeding module and the hopper dischargecontrol apparatus of the second feeding module.

In some embodiments of the present invention, the 3D printing devicefurther includes: a first temporary storage module, where the firsttemporary storage module includes a storage chamber having a feed inletand a discharge outlet, the feed inlet of the storage chamber isconnected to the discharge outlet of the processing chamber, thedischarge outlet of the storage chamber is connected to the firstprinting module, and the first temporary storage module is configured toreceive the first melt extruded from the discharge outlet of theprocessing chamber and guide the first melt to enter the first printingmodule through the discharge outlet of the storage chamber.

In some embodiments of the present invention, the first temporarystorage module further includes a storage chamber discharge controlapparatus, configured to control the discharge speed of the first meltat the discharge outlet of the storage chamber.

In some embodiments of the present invention, the first temporarystorage module further includes a storage chamber heating apparatus, andthe storage chamber heating apparatus is configured to heat the firstmelt in the storage chamber.

In some embodiments of the present invention, the 3D printing devicefurther includes: a third temperature measurement apparatus, where thethird temperature measurement apparatus is communicatively connected tothe control module, and configured to measure the temperature of thefirst melt in the storage chamber and transmit a third temperaturemeasurement signal to the control module; and the control modulecontrols heating power of the storage chamber heating apparatusaccording to the third temperature measurement signal.

In some embodiments of the present invention, the 3D printing devicefurther includes: a volume measurement apparatus, where the volumemeasurement apparatus is communicatively connected to the controlmodule, and configured to measure a remaining volume of the storagechamber and transmit a volume measurement signal to the control module.

In some embodiments of the present invention, the first melt extrusionmodule further includes: a melt extrusion discharge control apparatus,configured to control the discharge speed of the first melt at thedischarge outlet of the processing chamber; and the melt extrusiondischarge control apparatus is communicatively connected to the controlmodule, and the control module controls the discharge speed of the firstmelt at the discharge outlet of the processing chamber through the meltextrusion discharge control apparatus according to the volumemeasurement signal.

In some embodiments of the present invention, the 3D printing devicefurther includes: a backflow channel, where the backflow channel isconfigured to guide at least a part of the first melt extruded from thedischarge outlet of the processing chamber to flow back to theprocessing chamber.

In some embodiments of the present invention, the 3D printing devicefurther includes: a second feeding module, where the second feedingmodule includes a hopper having a feed inlet and a discharge outlet, andis configured to receive a second initial material through the feedinlet of the hopper and discharge the second initial material; a secondmelt extrusion module, where the second melt extrusion module includes aprocessing chamber having a feed inlet and a discharge outlet, and anextrusion apparatus and a processing chamber heating apparatus that aredisposed in the processing chamber, and is configured to receive thesecond initial material through the feed inlet of the processing chamberof the second melt extrusion module and heat and extrude the secondinitial material, so that the second initial material is converted intoa second melt and the second melt is extruded from the discharge outletof the processing chamber of the second melt extrusion module; and afirst mixing module, where the first mixing module includes a mixingchamber having a feed inlet and a discharge outlet, the feed inlet ofthe mixing chamber is connected to both the discharge outlet of theprocessing chamber of the first melt extrusion module and the dischargeoutlet of the processing chamber of the second melt extrusion module,the discharge outlet of the mixing chamber is connected to the firstprinting module, and the first mixing module is configured to receivethe extruded first melt and second melt, mix them into a first mixedmelt, and guide the first mixed melt to enter the first printing module.

In some embodiments of the present invention, the first melt extrusionmodule and the second melt extrusion module respectively include meltextrusion discharge control apparatuses, respectively configured tocontrol the discharge speed of the first melt at the discharge outlet ofthe processing chamber of the first melt extrusion module and thedischarge speed of the second melt at the discharge outlet of theprocessing chamber of the second melt extrusion module.

In some embodiments of the present invention, the 3D printing devicefurther includes: a second composition measurement apparatus, where thesecond composition measurement apparatus is communicatively connected tothe control module, and configured to measure a composition of the firstmixed melt extruded from the discharge outlet of the mixing chamber andtransmit a second composition measurement signal to the control module;and the melt extrusion discharge control apparatus of the first meltextrusion module and the melt extrusion discharge control apparatus ofthe second melt extrusion module are communicatively connected to thecontrol module, so that the control module controls, according to thesecond composition measurement signal, the discharge speed of the firstmelt at the discharge outlet of the processing chamber of the first meltextrusion module and the discharge speed of the second melt at thedischarge outlet of the processing chamber of the second melt extrusionmodule respectively through the melt extrusion discharge controlapparatus of the first melt extrusion module and the melt extrusiondischarge control apparatus of the second melt extrusion module.

In some embodiments of the present invention, the first mixing modulefurther includes a mixing chamber heating apparatus, and the mixingchamber heating apparatus is configured to heat the first mixed melt inthe mixing chamber.

In some embodiments of the present invention, the 3D printing devicefurther includes: a fourth temperature measurement apparatus, where thefourth temperature measurement apparatus is communicatively connected tothe control module, and configured to measure the temperature of thefirst mixed melt in the mixing chamber and transmit a fourth temperaturemeasurement signal to the control module; and the control modulecontrols heating power of the mixing chamber heating apparatus accordingto the fourth temperature measurement signal.

In some embodiments of the present invention, the first mixing modulefurther includes a mixing chamber discharge control apparatus,configured to control the discharge speed of the first mixed melt at thedischarge outlet of the mixing chamber.

In some embodiments of the present invention, an inner diameter of thefirst nozzle is 0.05 mm to 2 mm.

In some embodiments of the present invention, the first printing modulefurther includes a second nozzle.

In some embodiments of the present invention, a length of a connectionpath from the first nozzle to the discharge outlet of the processingchamber is equal to a length of a connection path from the second nozzleto the discharge outlet of the processing chamber.

In some embodiments of the present invention, the nozzle apparatusincludes a plurality of nozzles, and the nozzles are arranged in anarray.

In some embodiments of the present invention, the 3D printing devicefurther includes: a printing module driving mechanism, where theprinting module driving mechanism is configured to drive the firstnozzle of the first printing module to move relative to the platformmodule.

In some embodiments of the present invention, the printing moduledriving mechanism is configured to drive the first nozzle of the firstprinting module to move along a Z-axis of a Cartesian coordinate systemrelative to the platform module.

In some embodiments of the present invention, the platform moduleincludes: a first deposition platform, where the first depositionplatform is configured to receive the first melt extruded through thefirst nozzle; and a platform driving mechanism, where the platformdriving mechanism drives the first deposition platform to move relativeto the first nozzle of the first printing module.

In some embodiments of the present invention, the platform drivingmechanism is configured to drive the first deposition platform to movealong an X-axis and/or a Y-axis of a Cartesian coordinate systemrelative to the first nozzle.

In some embodiments of the present invention, the 3D printing devicefurther includes: a second melt extrusion module, where the second meltextrusion module includes a processing chamber having a feed inlet and adischarge outlet, and an extrusion apparatus and a processing chamberheating apparatus that are disposed in the processing chamber, and isconfigured to receive a second initial material through the feed inletof the processing chamber and heat and extrude the second initialmaterial, so that the second initial material is converted into a secondmelt and the second melt is extruded from the discharge outlet of theprocessing chamber; the first printing module further includes a secondnozzle, the second nozzle is connected to the discharge outlet of theprocessing chamber of the second melt extrusion module, and the firstprinting module is configured to receive the second melt extruded fromthe discharge outlet of the processing chamber of the second meltextrusion module and guide the second melt to be extruded through thesecond nozzle; and the platform driving mechanism drives the firstdeposition platform to move between a position below the first nozzleand a position below the second nozzle.

In some embodiments of the present invention, the platform modulefurther includes: a second deposition platform, where the seconddeposition platform is configured to receive the first melt extrudedthrough the first nozzle; and the platform driving mechanism drives thefirst deposition platform and the second deposition platform to passbelow the first nozzle in turn.

In some embodiments of the present invention, the 3D printing devicefurther includes a product collection module, where the productcollection module is configured to collect a final product formed on theplatform module.

In some embodiments of the present invention, the 3D printing devicefurther includes an inspection module, where the inspection module isconfigured to measure a product parameter of a final product formed onthe platform module.

In some embodiments of the present invention, the 3D printing devicefurther includes an automatic screening module, where the automaticscreening module is configured to pick a final product formed on theplatform module.

In some embodiments of the present invention, the 3D printing devicefurther includes an automatic conveyance module, where the automaticconveyance module is configured to convey the first initial material tothe first feeding module.

In some embodiments of the present invention, all of the foregoinginterconnected parts are connected through hoses.

In some embodiments of the present invention, inner diameters of thehoses are 1 mm to 100 mm.

In some embodiments of the present invention, the first initial materialincludes a thermoplastic material.

In some embodiments of the present invention, the 3D printing devicefurther includes a second printing module, where the second printingmodule is located above the first printing module along a Z-axis of aCartesian coordinate system.

In some embodiments of the present invention, the 3D printing devicefurther includes a plurality of the foregoing devices, where eachprinting module is equipped with a control switch. In some embodiments,the system includes a first device loaded with a first material and asecond device loaded with a second material, where the first material isdifferent from the second material. In some embodiments, the systemincludes a computer system, where the computer system includes one ormore processors and a computer readable memory, and the computer systemis configured to control the system. In some embodiments of the presentinvention, the computer readable memory stores an instruction forprinting a product by using the system. In some embodiments of thepresent invention, the computer readable memory stores an instructionfor controlling the pressure of a material in each printing module inresponse to a pressure measured by a pressure sensor of thecorresponding printing module. In some embodiments of the presentinvention, the computer readable memory stores an instruction forcontrolling the temperature of a material in each printing module inresponse to a temperature measured by a temperature sensor of thecorresponding printing module.

In another aspect of the present invention, a 3D printing method isprovided. The 3D printing method includes: feeding a first initialmaterial to a processing chamber of a first melt extrusion module;heating and extruding the first initial material in the processingchamber, so that the first initial material is converted into a firstmelt and the first melt is extruded from a discharge outlet of theprocessing chamber; and guiding the first melt at the discharge outletof the processing chamber to be extruded through a first nozzle of afirst printing module and deposited on a platform module.

In some embodiments of the present invention, the 3D printing methodfurther includes: feeding the first initial material to the first meltextrusion module through a hopper of a first feeding module.

In some embodiments of the present invention, the 3D printing methodfurther includes: measuring the pressure of the first melt in the firstprinting module; and controlling the pressure of the first melt in thefirst printing module according to the measured pressure. In someembodiments of the present invention, the method controls, by using afeedback system, the pressure of the first melt based on the monitoredpressure.

In some embodiments of the present invention, the pressure of the firstmelt in the nozzle remains approximately constant.

In some embodiments of the present invention, the 3D printing methodfurther includes: measuring the temperature of the first melt in thefirst printing module; and regulating the temperature of the first meltin the first printing module according to the measured temperature. Insome embodiments of the present invention, the method controls, by usinga feedback system, the temperature of the first melt based on themonitored temperature.

In some embodiments of the present invention, the temperature of thefirst melt in the nozzle remains approximately constant.

In some embodiments of the present invention, the step of guiding thefirst melt at the discharge outlet of the processing chamber to beextruded through the first nozzle of the first printing module anddeposited on the platform module includes: making the first melt flowthrough an extrusion port of the nozzle, where the nozzle includes atapered inner surface; making a tapered end of a sealing needle engagewith the tapered inner surface of the nozzle, to seal the extrusion portand inhibit flowing of the first melt; and withdrawing the tapered endof the sealing needle, to resume flowing of the first melt through theextrusion port.

In some embodiments of the present invention, the first melt includes apharmaceutically acceptable material. In some embodiments, the firstmelt includes a drug. In some embodiments, the method includes:receiving an instruction for manufacturing a pharmaceutical dosage form.

In some embodiments of the present invention, the material isnon-filamentous. In some embodiments, the material has a viscosity ofabout 100 Pa·s or more.

In some embodiments of the present invention, any portion of the sealingneedle that contacts the material is free of protrusions.

In some embodiments of the present invention, the tapered end of thesealing needle includes a sharp pointed tip. In some embodiments, thetapered end of the sealing needle is frustoconical. In some embodiments,the tapered inner surface of the nozzle has a first taper angle, and thetapered end of the sealing needle has a second taper angle, where thesecond taper angle is equal to or less than the first taper angle. Insome embodiments, the second taper angle is about 60° or less. In someembodiments, the second taper angle is about 45° or less. In someembodiments, a ratio of the first taper angle to the second taper angleis about 1:1 to 4:1. In some embodiments, the extrusion port has adiameter of about 0.1 mm to 1 mm. In some embodiments, the tapered endhas a largest diameter of about 0.2 mm to about 3.0 mm. In someembodiments, the extrusion port has a diameter, and the tapered end hasa largest diameter, where a ratio of the largest diameter of the taperedend to the diameter of the extrusion port is about 1:0.8 to about 1:0.1.

In some embodiments of the present invention, the method controls, byusing a feedback system, the pressure of the first melt based on themonitored pressure. In some embodiments of the present invention, thepressure of the first melt in the nozzle remains approximately constant.

In some embodiments of the present invention, the method controls, byusing a feedback system, the temperature of the first melt based on themonitored temperature. In some embodiments of the present invention, thetemperature of the first melt in the nozzle remains approximatelyconstant. In some embodiments of the present invention, the 3D printingmethod further includes: measuring the temperature of the first melt inthe processing chamber; and controlling heating power and/or extrusionpower for the first melt or the first initial material in the processingchamber according to the measured temperature.

In some embodiments of the present invention, the step of guiding thefirst melt at the discharge outlet of the processing chamber to beextruded through the first nozzle of the first printing module anddeposited on the platform module includes: guiding the first melt at thedischarge outlet of the processing chamber to enter a storage chamber ofa first temporary storage module; and guiding the first melt at adischarge outlet of the storage chamber to be extruded through the firstnozzle of the first printing module and deposited on the platformmodule. In some embodiments of the present invention, the 3D printingmethod further includes: measuring the temperature of the first melt inthe storage chamber; and controlling heating power for the first melt inthe storage chamber according to the measured temperature.

In some embodiments of the present invention, the 3D printing methodfurther includes: measuring a remaining volume of the storage chamber;and controlling the discharge speed of the first melt at the dischargeoutlet of the processing chamber according to the remaining volume ofthe storage chamber.

In some embodiments of the present invention, the 3D printing methodfurther includes: guiding at least a part of the first melt extrudedfrom the discharge outlet of the processing chamber to flow back to theprocessing chamber.

In some embodiments of the present invention, the 3D printing methodfurther includes: feeding a second initial material to a processingchamber of a second melt extrusion module through a hopper of a secondfeeding module; heating and extruding the second initial material in theprocessing chamber of the second melt extrusion module, so that thesecond initial material is converted into a second melt and the secondmelt is extruded from a discharge outlet of the processing chamber ofthe second melt extrusion module; mixing the first melt and the secondmelt in a mixing chamber, to form a first mixed melt; and guiding thefirst mixed melt at a discharge outlet of the mixing chamber to beextruded through the first nozzle of the first printing module anddeposited on the platform module.

In some embodiments of the present invention, the 3D printing methodfurther includes: measuring a composition of the first mixed meltextruded from the discharge outlet of the mixing chamber; andcontrolling the discharge speed of the first melt at the dischargeoutlet of the processing chamber of the first melt extrusion module andthe discharge speed of the second melt at the discharge outlet of theprocessing chamber of the second melt extrusion module respectivelyaccording to the measured composition of the first mixed melt.

In some embodiments of the present invention, the 3D printing methodfurther includes: measuring the temperature of the first mixed melt inthe mixing chamber; and controlling heating power for the first mixedmelt in the mixing chamber according to the measured temperature.

In some embodiments of the present invention, the 3D printing methodfurther includes: feeding a second initial material to the processingchamber of the first melt extrusion module through a hopper of a secondfeeding module; and heating and extruding the first initial material andthe second initial material in the processing chamber, so that they areconverted into a first melt.

In some embodiments of the present invention, the 3D printing methodfurther includes: measuring a composition of the first melt at anyposition of a 3D printing device, and controlling the discharge speed ofthe first initial material at a discharge outlet of the first feedingmodule and the discharge speed of the second initial material at adischarge outlet of the second feeding module respectively according tothe measured composition of the first melt.

In some embodiments of the present invention, the 3D printing methodfurther includes: feeding a second initial material to a processingchamber of a second melt extrusion module through a hopper of a secondfeeding module; and heating and extruding the second initial material inthe processing chamber of the second melt extrusion module, so that thesecond initial material is converted into a second melt and the secondmelt is extruded from a discharge outlet of the processing chamber ofthe second melt extrusion module; guiding the second melt at thedischarge outlet of the processing chamber of the second melt extrusionmodule to be extruded through a second nozzle of the first printingmodule and deposited on the platform module; and driving the platformmodule to move between a position below the first nozzle and a positionbelow the second nozzle.

In some embodiments of the present invention, the 3D printing methodfurther includes: monitoring the pressure of the first melt within thefirst nozzle or proximal to the first nozzle; or monitoring the pressureof the second melt in the second nozzle or proximal to the secondnozzle. In some embodiments, the pressure of the first melt in the firstnozzle or the pressure of the second melt in the second nozzle remainsapproximately constant. In some embodiments, the method includes:controlling, by using a feedback system, the pressure of the first meltor the second melt based on the monitored pressure.

In some embodiments of the foregoing method, the first melt or thesecond melt has a viscosity of about 100 Pa·s or higher.

In some embodiments of the present invention, the first initial materialor the second initial material is non-filamentous.

In some embodiments of the present invention, any portion of a firstsealing needle that contacts the first melt or any portion of a secondsealing needle that contacts the second melt is free of protrusions.

In some embodiments of the present invention, the temperature of thefirst melt in the first nozzle or the temperature of the second melt inthe second nozzle remains approximately constant. In some embodiments,the method includes: monitoring the temperature of the first melt or thetemperature of the second melt. In some embodiments, the methodincludes: controlling, by using a feedback system, the temperature ofthe first melt based on the monitored temperature of the first melt; orcontrolling, by using a feedback system, the temperature of the secondmelt based on the monitored temperature of the second melt.

In some embodiments of the present invention, a tapered end of the firstsealing needle or a tapered end of the second sealing needle includes apointed tip. In some embodiments of the foregoing method, the taperedend of the first sealing needle or the tapered end of the second sealingneedle is frustoconical.

In some embodiments of the present invention, the tapered inner surfaceof the first nozzle has a first taper angle, and the tapered end of thefirst sealing needle has a second taper angle, where the second taperangle is equal to or less than the first taper angle; or a tapered innersurface of the second nozzle has a third taper angle, and the taperedend of the second sealing needle has a fourth taper angle, where thefourth taper angle is equal to or less than the third taper angle. Insome embodiments of the present invention, the fourth taper angle isabout 60° or less. In some embodiments of the present invention, thesecond taper angle or the fourth taper angle is about 45° or less. Insome embodiments of the present invention, a ratio of the first taperangle to the second taper angle or a ratio of the third taper angle tothe fourth taper angle is about 1:1 to about 4:1. In some embodiments ofthe present invention, a first extrusion port or a second extrusion porthas a diameter of about 0.1 mm to about 1 mm. In some embodiments of thepresent invention, the tapered end of the first sealing needle or thetapered end of the second sealing needle has a largest diameter of about0.2 mm to about 3.0 mm. In some embodiments of the present invention,the 3D printing method further includes: driving the first nozzle of thefirst printing module to move relative to the platform module.

In some embodiments of the present invention, the 3D printing methodfurther includes: driving the first nozzle of the first printing moduleto move along a Z-axis of a Cartesian coordinate system relative to theplatform module.

In some embodiments of the present invention, the 3D printing methodfurther includes: driving a first deposition platform of the platformmodule to move relative to the first nozzle of the first printingmodule, where the first deposition platform is configured to receive thefirst melt extruded through the first nozzle.

In some embodiments of the present invention, the 3D printing methodfurther includes: driving the first deposition platform to move along anX-axis and/or a Y-axis of a Cartesian coordinate system relative to thefirst nozzle.

In some embodiments of the present invention, the 3D printing methodfurther includes: collecting a final product formed on the platformmodule.

In some embodiments of the present invention, the 3D printing methodfurther includes: measuring a product parameter of a final productformed on the platform module.

In some embodiments of the present invention, the 3D printing methodfurther includes: picking a final product formed on the platform module.

In some embodiments of the present invention, the 3D printing methodfurther includes: conveying the first initial material to the firstfeeding module through an automatic conveyance module.

In some embodiments of the present invention, the first initial materialincludes a thermoplastic material.

In another aspect of the present invention, a printing module used in a3D printing device is provided. The printing module includes n×m nozzlesarranged in an array (both n and m are integers greater than or equal to2), where a position of a nozzle (x, y) is in an x^(th) column and ay^(th) row (1≤x≤n, and 1≤y≤m).

In some embodiments of the present invention, the printing module isconstructed to be capable of extruding m types of melt, and the nozzle(x, y) is constructed to be capable of extruding a y^(th) type of melt.

In some embodiments of the present invention, the n×m nozzles arerespectively connected to n×m processing chambers.

In some embodiments of the present invention, the discharge speeds ofthe n×m nozzles are respectively controlled by n×m melt extrusiondischarge control apparatuses.

In some embodiments of the present invention, nozzles in the y^(th) rowof the n×m nozzles are configured to have almost a same discharge speed.In another aspect of the present invention, a 3D printing method isprovided. The 3D printing method includes: melting and pressurizing amaterial; making the material flow through an extrusion port of anozzle, where the nozzle includes a tapered inner surface; monitoringthe pressure of the material in the nozzle or close to the nozzle;making a tapered end of a sealing needle engage with the tapered innersurface of the nozzle, to seal the extrusion port and inhibit flowing ofthe melted material; and withdrawing the tapered end of the sealingneedle, to resume flowing of the material through the extrusion port. Insome embodiments, the method includes: receiving an instruction formanufacturing a product.

In some embodiments of the present invention, the 3D printing methodfurther includes: melting and pressurizing a first material; making thefirst material flow through a first extrusion port of a first nozzlethat includes a tapered inner surface; making a tapered end of a firstsealing needle engage with the tapered inner surface of the firstnozzle, to seal the first extrusion port and inhibit flowing of themelted first material; melting and pressurizing a second material; andwithdrawing a tapered end of a second sealing needle from a taperedinner surface of a second nozzle, so that the second material flowsthrough a second extrusion port. In some embodiments of the presentinvention, the method includes: receiving an instruction formanufacturing a product.

In another aspect, a method for manufacturing a pharmaceutical dosageform through 3D printing is provided. The method includes: melting andpressurizing a first pharmaceutical material; making the firstpharmaceutical material flow through a first extrusion port of a firstnozzle that includes a tapered inner surface; making a tapered end of afirst sealing needle engage with the tapered inner surface of the firstnozzle, to seal the first extrusion port and inhibit flowing of themelted first pharmaceutical material; melting and pressurizing a secondpharmaceutical material; and withdrawing a tapered end of a secondsealing needle from a tapered inner surface of a second nozzle, so thatthe second pharmaceutical material flows through a second extrusionport. In some embodiments of the present invention, the firstpharmaceutical material or the second pharmaceutical material is anerodible material. In some embodiments of the present invention, thefirst pharmaceutical material or the second pharmaceutical materialincludes a drug. In some embodiments, a pharmaceutical dosage form has aspecific drug release profile. In some embodiments of the presentinvention, the method further includes: receiving a control instructionfor manufacturing a pharmaceutical dosage form.

In some embodiments of the present invention, a product or apharmaceutical dosage form is manufactured in batches. In someembodiments of the foregoing methods, a product or a pharmaceuticaldosage form is manufactured in a continuous mode.

The present invention further provides a product or pharmaceuticaldosage form manufactured according to any one of the foregoing methods.

BRIEF DESCRIPTION OF THE DRAWINGS

The following details described with reference to the accompanyingdrawings and the appended claims will facilitate a clearer understandingof the foregoing and other features of the present application. Itshould be understood that, the accompanying drawings of the presentapplication merely show some embodiments of the present invention, andtherefore shall not be construed as any limitation on the scope of thepresent invention. Unless otherwise stated, the accompanying drawingsare not necessarily proportional and similar labels generally representsimilar parts.

FIG. 1 illustrates a schematic diagram of a 3D printing device accordingto a particular embodiment of the present invention.

FIG. 2 illustrates a schematic diagram of a 3D printing device accordingto another embodiment of the present invention.

FIG. 3 illustrates a schematic diagram of a 3D printing device accordingto another embodiment of the present invention.

FIG. 4 illustrates a perspective view of a 3D printing device accordingto a particular embodiment of the present invention.

FIG. 5 illustrates a schematic diagram of arrangement of nozzles of a 3Dprinting device on a printing module according to a particularembodiment of the present invention.

FIG. 6 illustrates a schematic diagram of a 3D printing device accordingto another embodiment of the present invention.

FIG. 7A and FIG. 7B each illustrate a model of a pharmaceutical productthat can be printed by using a 3D printing device according to aparticular embodiment of the present invention.

FIG. 8 illustrates a flowchart of a 3D printing method according to aparticular embodiment of the present invention.

FIG. 9A illustrates a schematic diagram of a 3D printing deviceaccording to another embodiment of the present invention.

FIG. 9B illustrates a perspective view of a 3D printing device accordingto another embodiment of the present invention.

FIG. 9C illustrates an enlarged view of a printing head according toanother embodiment of the present invention.

FIG. 9D illustrates an exploded view of components of a pneumaticactuator configured to control a sealing needle according to anotherembodiment of the present invention.

FIGS. 10A-10C illustrate an enlarged view of a sealing needle and anextrusion port according to another embodiment of the present invention.

FIG. 11 illustrates a schematic diagram of a 3D printing deviceaccording to another embodiment of the present invention.

FIG. 12 illustrates a schematic diagram of a 3D printing deviceaccording to another embodiment of the present invention.

FIGS. 13A-13C illustrate a schematic diagram of a 3D printing deviceaccording to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description is given with reference to theaccompanying drawings, which are a part of this specification. In theaccompanying drawings, similar symbols generally represent similar partsunless otherwise stated. The detailed description, the accompanyingdrawings, and illustrative embodiments described in the claims are notintended for limitation. Other embodiments may be used and other changesmay be made without departing from the spirit or scope of the subjectmatter of the present application. It may be understood that, forvarious aspects of the content generally described herein andillustrated in the accompanying drawings, a plurality of configurations,replacements, combinations, and designs with different composition maybe made, and all these explicitly constitute a part of the content ofthe present invention.

The following describes specific embodiments of the present inventionwith reference to the accompanying drawings. FIG. 1 illustrates aschematic diagram of a 3D printing device according to a particularembodiment of the present invention.

As shown in FIG. 1, a 3D printing device 100 includes a melt extrusionmodule 102, a printing module 103, and a platform module 104. In aprinting process of the device, the melt extrusion module 102 extrudesand heats a received initial material so that the initial material ismelted into a melt, and conveys the melt to the printing module 103; theprinting module 103 extrudes the melt toward a specified position of theplatform module 104 according to a preset data model or program; and themelt is stacked and piled up on the platform 104, to ultimately form a3D product needing to be printed.

As shown in FIG. 1, in some embodiments, the 3D printing device mayfurther include a feeding module 101, where the feeding module 101 has ahopper 111 configured to accommodate and convey the initial material,and the hopper 111 has a feed inlet 112 and a discharge outlet 113. Inthe printing process of the 3D printing device 100, the feeding module101 receives the initial material through the feed inlet 112 of thehopper 111, and discharges the initial material to the melt extrusionmodule 102 through the discharge outlet 113. The initial material usedin the 3D printing device 100 may be a powdered or granular material. Asshown in FIG. 1, the hopper 111 is a funnel-shaped shell having ahorn-like opening. In some embodiments, the initial material mayalternatively be filamentous, block-like, or another shape; andcorrespondingly, the hopper may have a corresponding shape to adapt tothe shape of the initial material. A hopper discharge control apparatus114 is further disposed in the hopper 111. The hopper discharge controlapparatus 114 controls the discharge speed of the initial material atthe discharge outlet 113 of the hopper 111. The hopper discharge controlapparatus 114 shown in FIG. 1 is a single screw. Disposed at a positionclose to the discharge outlet, the hopper discharge control apparatus114 is connected to a motor and a gearing apparatus (not shown inFIG. 1) that drive the hopper discharge control apparatus 114 to move.The rotational speed of the screw 114 is regulated through a drivingmechanism, to control the discharge speed of the initial material at thedischarge outlet 113. In addition, a mixing and conveying manner of thematerial can be controlled by disposing a pitch and a thread of a screwportion of the screw 114. Although the hopper discharge controlapparatus 114 shown in FIG. 1 is a single screw, in some embodiments,the hopper discharge control apparatus may alternatively be twin screws,or a combination of twin screws and a single screw. In some embodiments,the hopper discharge control apparatus 114 may further include a commonmechanism capable of controlling the discharge speed of the initialmaterial at the discharge outlet 113. In some embodiments, the hopperdischarge control apparatus further includes a baffle plate or a barrierdisposed at the discharge outlet 113, to control whether to dischargethe material from the discharge outlet 113. In some embodiments, thehopper discharge control apparatus 114 may alternatively be a flowcontrol valve disposed at the discharge outlet 113, for example, apneumatic flow control valve, a solenoid flow control valve, or ahydraulic flow control valve, to control the discharge speed of theinitial material at the discharge outlet 113 through the size of theflow control valve.

The 3D printing device 100 may further include a second feeding module201. As shown in the figure, a structure of the second feeding module201 is the same as or similar to that of the first feeding module 101.The second feeding module 201 similarly includes a second hopper 211having a feed inlet 212 and a discharge outlet 213, and similarlyincludes a hopper discharge control apparatus 214 disposed in the hopper211, where the hopper discharge control apparatus 214 is configured tocontrol the discharge speed of the initial material at the dischargeoutlet 212. In a specific printing process of the device, the feedingmodule 201 may receive, through the feed inlet 212 of the hopper 211, asecond initial material different from the initial material received bythe feeding module 101; and discharge the second initial material to themelt extrusion module 102 through the discharge outlet 213. It may beunderstood that, a ratio of the initial material received by the meltextrusion module 102 to the second initial material can be controlled bycontrolling the hopper discharge control apparatus 114 of the feedingmodule 101 and the hopper discharge control apparatus 214 of the secondfeeding module 201, to ultimately control the ratio of the initialmaterial to the second initial material in a product needing to beprinted.

As shown in FIG. 1, the melt extrusion module 102 includes a processingchamber 121, an extrusion apparatus 122, and a processing chamberheating apparatus 123. The processing chamber 121 is a hollow shellhaving a feed inlet 124 and a discharge outlet 125, and the initialmaterial discharged from the discharge outlet 113 enters the processingchamber 121 through the feed inlet 124. The processing chamber heatingapparatus 123 is disposed on a peripheral wall of the processing chamber121, to heat the material within the processing chamber 121. Theextrusion apparatus 122 does work of extruding and/or shearing thematerial within the processing chamber 121, so that the initial materialis melted into a melt and discharged through the discharge outlet 125under a joint action of the processing chamber heating apparatus 123 andthe extrusion apparatus 122.

Specifically, as shown in FIG. 1, the extrusion apparatus 122 may betwin screw 122 disposed in the processing chamber 121. The twin screw122 are connected to a driving motor 129 through a variable-speed gear128. Driven by the driving motor 129, the twin screw 122 rotate andextrude the material within the processing chamber 121, and drive thematerial to move toward the discharge outlet 125. Meanwhile, thematerial within the processing chamber 121 is heated by internal heatthat is generated by the rotation and extrusion work of the twin screw122. Although the extrusion apparatus 122 shown in FIG. 1 is twin screw,in some embodiments, the hopper discharge control apparatus mayalternatively be a single screw. In some embodiments, the extrusionapparatus 122 may alternatively be a common extruder without any screw,for example, a piston apparatus.

As shown in FIG. 1, the processing chamber heating apparatus 123 may besuch disposed as to surround an exterior wall of the processing chamber121 in a segment-by-segment manner, to perform segment-by-segmentheating, so as to implement more precise heating temperature control. Insome embodiments, the processing chamber heating apparatus 123 is acommon electrical heating apparatus, for example, a thermocouple wrappedaround an outer side of the processing chamber 121. It may be understoodthat, although the processing chamber heating apparatus 123 shown in thefigure is disposed on the exterior wall of the processing chamber 121,in some embodiments, the processing chamber heating apparatus 123 mayalternatively be disposed in the processing chamber 121, for example, aheating rod disposed in the processing chamber 121.

In some embodiments, the melt extrusion module 102 further has a meltextrusion discharge control apparatus 126 (not shown in FIG. 1),configured to control the discharge speed of the melt at the dischargeoutlet 125 of the processing chamber 121. Similar to the structure ofthe hopper discharge control apparatus 114, the melt extrusion dischargecontrol apparatus 126 may be a flow control valve disposed at thedischarge outlet 125, for example, a pneumatic flow control valve, ahydraulic flow control valve, or a solenoid flow control valve, wherethe discharge speed of the melt at the discharge outlet 125 iscontrolled through the flow control valve. In some embodiments, the meltextrusion discharge control apparatus 126 may further have a baffleplate or a barrier disposed at the discharge outlet 125, to controlwhether to discharge the melt from the discharge outlet 125. It shouldbe noted that, the extrusion apparatus 122 of the melt extrusion module102 can control the discharge speed of the melt at the discharge outlet125 by controlling extrusion power for extruding the initial materialand the melt in the processing chamber 121. Specifically, in the twinscrew 122 shown in FIG. 1, the discharge speed of the melt at thedischarge outlet 125 can be controlled by controlling the rotation speedof the twin screw 122. In some embodiments, the discharge speed of thedischarge outlet 125 of the melt extrusion module 102 can be regulatedby controlling the feed speed of the feed inlet 124. Specifically, forexample, the discharge speed of the discharge outlet 125 may be improvedby improving the feed speed of the feed inlet 124. The feed speed of thefeed inlet 124 of the melt extrusion module 102 can be implemented byregulating the discharge speed of the discharge outlet 113 of thefeeding module 101.

In some embodiments, the 3D printing device 100 further includes abackflow channel 127 (not shown in FIG. 1). One end of the backflowchannel 127 is connected to a melt channel behind the discharge outlet125 of the processing chamber 121, and the other end of the backflowchannel 127 is connected to the processing chamber 121, so that a partof the melt flows back to the processing chamber 121. In someembodiments, the backflow channel 127 is further equipped with a flowcontrol valve, so that an amount of and the speed of a melt flowing backthrough the backflow channel 127 to the processing chamber 121 areregulated through the flow control valve.

As shown in FIG. 1 again, the printing module 103 may include a barrel133 having a feed inlet and a discharge outlet. The barrel 133 iscomposed of a hollow shell, and a nozzle 131 is disposed at a lower partof the barrel 133. The feed inlet of the barrel 133 of the printingmodule 103 is connected to the discharge outlet 125 of the processingchamber 121. After the initial material is heated and melted into amelt, the melt is conveyed to the barrel 133 and ultimately extrudedthrough the nozzle 131. Although the printing module 103 shown in FIG. 1has only one nozzle 131, in some embodiments, the printing module 103may include a plurality of nozzles, to implement batch production,thereby resolving a common defect of prior-art 3D printing devices offused deposition modeling, namely, a mass production failure. Theplurality of nozzles may be arranged in an array, or arranged accordingto another rule applicable to mass production. A specific manner ofarrangement of the nozzles is described in detail later with referenceto the accompanying drawings. The printing module 103 further includes aprinting module driving mechanism 132 (not shown in FIG. 1). The drivingmechanism 132 may be a hydraulic cylinder, a stepper motor, or anothercommon driving mechanism. The printing module 103 is disposed on thedriving mechanism 132, so that the nozzle 131 of the printing module 103is driven to move relative to the platform module 104. As shown in FIG.1, the barrel 133 of the printing module 103 may alternatively beequipped with a temperature regulating apparatus 134. A structure andarrangement of the temperature regulating apparatus 134 are the same asor similar to those of the processing chamber heating apparatus 123, andmay be an electrical heating apparatus disposed around the barrel 133 ina segment-by-segment manner. In some embodiments, the temperatureregulating apparatus 134 may alternatively be a heating rod disposed inthe barrel 133. It should be noted that, the temperature regulatingapparatus may further have a cooling function, for example, asemiconductor heating and cooling sheet, so that the temperature of themelt in the printing module 103 can be reduced if too high. Thetemperature regulating apparatus 134 is preferably disposed at aposition close to the nozzle 131, so as to quickly and precisely controlthe temperature of the melt extruded through the nozzle 131. The barrel133 further includes a pressure regulating apparatus (not shown in FIG.1), configured to regulate the pressure of the melt in the printingmodule 103. In some embodiments, the pressure regulating apparatus maybe a screw extrusion apparatus as described previously, specifically: asingle screw extruder, twin screw extruder, or a combination of a singlescrew extruder and twin screw extruder, where the screw extrusionapparatus is disposed in the barrel 133, and controls extrusion powerfor the melt through screw rotation control, thereby controlling thepressure of the melt in the printing module 103, especially in thenozzle 131. In some other embodiments, the pressure regulating apparatusmay alternatively be a piston extrusion mechanism, where the pistonextrusion mechanism is disposed in the barrel 133 and pneumatically orhydraulically drives a piston to move, thereby controlling the pressureof the melt in the printing module 103, especially in the nozzle 131.

As shown in FIG. 1, the platform module 104 includes a depositionplatform 141 and a platform driving mechanism 142 that drives thedeposition platform 141 to move. The deposition platform 141 may be aplate structure, and is configured to receive the melt extruded throughthe nozzle 131, so that the melt is stacked on the deposition platform.Although only one deposition platform 141 is shown in FIG. 1, in someembodiments, the platform module 104 may further include a plurality ofdeposition platforms, to satisfy a mass production requirement duringsimultaneous mass printing. Structures between a plurality of depositionplatforms are described in detail later with reference to otheraccompanying drawings.

The deposition platform 141 is disposed on the platform drivingmechanism 142. The platform driving mechanism 142 can drive thedeposition platform 141 to move relative to the nozzle 131. In someembodiments, the platform driving mechanism 142 may be a stepper motordisposed based on a Cartesian coordinate system, so that the platformdriving mechanism 142 can drive the deposition platform 141 to movealong one or more of an X-axis, a Y-axis, and a Z-axis. In some otherembodiments, the 3D printing device 100 further includes a printingmodule driving mechanism, configured to drive the nozzle 131 of theprinting module 103 to move relative to the platform module 104. Instill some embodiments, the platform driving mechanism 142 may be aconveyor belt. With relative motion between the deposition platform 141and the nozzle 131, the melt is deposited on the deposition platform141, to form final products of complex structures and composition asrequired.

As shown in FIG. 1 again, the 3D printing device 100 further includes atemporary storage module 107. The temporary storage module 107 has astorage chamber 171 configured to store a melt. The storage chamber 171has a feed inlet 172 and a discharge outlet 173. The feed inlet 172 isconnected to the discharge outlet of the processing chamber 121. Thedischarge outlet 173 is connected to the printing module 103 through afeed channel 135. The melt extruded from the discharge outlet of theprocessing chamber 121 flows through the feed inlet 172 into the storagechamber 171 for temporary storage, and flows through the dischargeoutlet 173 into the printing module 103 for printing. As shown in thefigure, the temporary storage module 107 further has a heating apparatus174 configured to heat the melt in the storage chamber 171, and theheating apparatus 174 is disposed on an exterior wall of the storagechamber 171. In some embodiments, the heating apparatus 174 is athermocouple surrounding the storage chamber 171. In some embodiments,the heating apparatus 174 may alternatively be disposed in the storagechamber 171, for example, a heating rod disposed in the storage chamber171. In some embodiments, an insulating liner is further disposed on theexterior wall of the storage chamber 171, to preserve heat for the meltin the storage chamber.

In some embodiments, the temporary storage module 107 further includes astorage chamber discharge control apparatus 175 (not shown in FIG. 1),configured to control the discharge speed of the melt at the dischargeoutlet 173 of the storage chamber 171. Similar to the hopper dischargecontrol apparatus 114, the storage chamber discharge control apparatus175 may be a single screw or twin screw disposed at a position close tothe discharge outlet 173, or a combination of a single screw or twinscrew, or a flow control valve disposed at the discharge outlet 173, forexample, a pneumatic flow control valve, a solenoid flow control valve,or a hydraulic flow control valve. In some embodiments, a baffle plateor a barrier is further disposed at the discharge outlet 173 of thestorage chamber 171, to control whether to discharge the melt from thedischarge outlet 173.

FIG. 2 illustrates a schematic diagram of a 3D printing device accordingto another embodiment of the present invention.

As shown in FIG. 2, a 3D printing device 200 further includes a firstfeeding module 301 and a second feeding module 401 that are disposed inparallel to each other, and a first melt extrusion module 302 and asecond melt extrusion module 402 that are disposed in parallel to eachother. Structures of the foregoing modules are the same as structures ofthe first feeding module 101 and the first melt extrusion module 102 asdescribed previously. The first feeding module 301 and the secondfeeding module 401 receive initial materials. The initial materials arerespectively heated and extruded through the first melt extrusion module302 and the second melt extrusion module 402 and are converted intomelts. The melts are discharged, and enter a mixing module 308.

As shown in FIG. 2 again, the 3D printing device 200 further includes amixing module 308. The mixing module 308 includes a mixing chamber 381having a feed inlet 382 and a discharge outlet 383. The feed inlet 382of the mixing chamber 381 is connected to the first melt extrusionmodule 302 and the second melt extrusion module 402. A mixing mechanism386 (not shown in FIG. 2) is disposed in the mixing chamber 308, and isconfigured to mix different melts that come from the first meltextrusion module 302 and the second melt extrusion module 402. In someembodiments, the mixing mechanism 386 is a mechanical stirringapparatus. In some other embodiments, however, the mixing mechanism 386may alternatively be a pneumatic stirring mechanism.

In some embodiments, the mixing module 308 further has a heatingapparatus 384, configured to heat and preserve heat for the melt in themixing chamber 381. The heating apparatus 384 may be disposed on anexterior wall of the mixing chamber 381. In some embodiments, theheating apparatus 384 is a thermocouple surrounding the mixing chamber381. In some embodiments, the heating apparatus 384 may alternatively bedisposed in the mixing chamber 381, for example, a heating rod disposedin the mixing chamber 381.

In some embodiments, the mixing module 308 further includes a mixingchamber discharge control apparatus 385 (not shown in FIG. 2),configured to control the discharge speed of the melt at the dischargeoutlet 383 of the mixing chamber 381. Similar to the hopper dischargecontrol apparatus 114, the mixing chamber discharge control apparatus385 may be a single screw or twin screw disposed at a position close tothe discharge outlet 383, or a combination of a single screw or twinscrew, or a flow control valve disposed at the discharge outlet 383, forexample, a pneumatic flow control valve, a solenoid flow control valve,or a hydraulic flow control valve. In some embodiments, a baffle plateor a barrier is further disposed at the discharge outlet 383 of themixing chamber, to control whether to discharge the melt from thedischarge outlet 383. The mixing module 308 may enable sufficient mixingof some solid-state initial materials that cannot be sufficiently mixedor can hardly be mixed, to form an even mixed melt, so that the mixedmelt discharged from the discharge outlet 383 enters a printing module303 and is stacked on a platform module 304 after being extruded througha nozzle 331, thereby forming a final product with mixed components.

FIG. 9A illustrates a schematic diagram of a printing module and anozzle according to a particular embodiment of the present invention.The device includes a barrel 133, configured to melt and pressurize amaterial. The melted and pressurized material flows through a feedchannel, where the feed channel is connected to a nozzle 131. A pressuresensor 106 is positioned proximal to the nozzle and the terminus of thefeed channel, and can measure the pressure of the material within thefeed channel. Optionally, the pressure sensor 106 can be designed todirectly measure the pressure of the material within the nozzle 131. Acontrol switch 108 includes a linear actuator and a sealing needle, andcan control the sealing needle to switch between an open position and aclosed position. The linear actuator may be a mechanical actuator (whichmay include a screw), a hydraulic actuator, a pneumatic actuator (whichmay include a pneumatic valve), or a solenoid actuator (which mayinclude a solenoid valve). In some embodiments, the actuator includes apin cylinder, for example, a pneumatic pin cylinder. In someembodiments, the actuator includes a spring-assisted pneumatic cylinder.In some embodiments, the spring-assisted pneumatic cylinder includes aspring that assists the sealing needle in acting (i.e. pull the sealingneedle to move from the open position to the closed position). In someembodiments, the spring-assisted pneumatic cylinder includes a springthat assists in withdrawing the sealing needle (i.e. pulling the sealingneedle to move from the closed position to the open position). When thesealing needle is in the open position, the pressurized melted materialcan flow through the feed channel and flow through an extrusion port ofthe nozzle 131. When a signal is sent to the control switch 108, thecontrol switch 108 lowers the sealing needle to the closed position, anda tip of the sealing needle engages with an inner surface of the nozzle131.

In some embodiments of the present invention, the material is anon-filamentous material, such as powder, a granule, a gel, or a paste.The non-filamentous material is melted and pressurized, so that it canbe extruded through the extrusion port of the nozzle. As describedfurther herein, the pressure of a particularly viscous material isprecisely controlled to ensure precise and accurate depositing of thematerial. The material can be heated and melted in the printing moduleby using one or more heaters disposed in the printing module (forexample, inside or surrounding a barrel, a feed channel, and/or aprinting head). In some embodiments, the melting temperature of thematerial is about 50° C. or higher, for example, about 60° C. or higher,about 70° C. or higher, about 80° C. or higher, about 100° C. or higher,about 120° C. or higher, about 150° C. or higher, about 200° C. orhigher, or about 250° C. or higher. In some embodiments, the meltingtemperature of the material is about 400° C. or lower, for example,about 350° C. or lower, about 300° C. or lower, about 260° C. or lower,about 200° C. or lower, about 150° C. or lower, about 100° C. or lower,or about 80° C. or lower. The material extruded from the nozzle can beextruded at a temperature equal to or higher than the meltingtemperature of the material. In some embodiments, the material isextruded at a temperature of about 50° C. or higher, for example, about60° C. or higher, about 70° C. or higher, about 80° C. or higher, about100° C. or higher, about 120° C. or higher, about 150° C. or higher,about 200° C. or higher, or about 250° C. or higher. In someembodiments, the material is extruded at a temperature of about 400° C.or lower, for example, about 350° C. or lower, about 300° C. or lower,about 260° C. or lower, about 200° C. or lower, about 150° C. or lower,about 100° C. or lower, or about 80° C. or lower.

The device according to the present invention is useful for accuratelyand precisely extruding a viscous material. In some embodiments, whenextruded from the device, the material has a viscosity of about 100 Pa·sor higher, for example, about 200 Pa·s or higher, about 300 Pa·s orhigher, about 400 Pa·s or higher, about 500 Pa·s or higher, about 750Pa·s or higher, or about 1000 Pa·s or higher. In some embodiments, thematerial has a viscosity of about 2000 Pa·s or lower, for example, about1000 Pa·s or lower, about 750 Pa·s or lower, about 500 Pa·s or lower,about 400 Pa·s or lower, about 300 Pa·s or lower, or about 200 Pa·s orlower.

In some embodiments, the material is a pharmaceutical material. In someembodiments, the material is inert or biologically inert. In someembodiments, the material is an erodible material or a bio-erodiblematerial. In some embodiments, the material is a non-erodible materialor a non-bio-erodible material. In some embodiments, the material is apharmaceutical material. In some embodiments, the material includes oneor more thermoplastic materials, one or more non-thermoplasticmaterials, or a combination of one or more thermoplastic materials andone or more non-thermoplastic materials. In some embodiments, thematerial is a polymer or a co-polymer.

In some embodiments, the material includes a thermoplastic material. Insome embodiments, the material is a thermoplastic material. In someembodiments, the material is or includes an erodible thermoplasticmaterial. In some embodiments, the thermoplastic material is edible(i.e. suitable for consumption by an individual). In some embodiments,the thermoplastic material is selected from a hydrophilic polymer, ahydrophobic polymer, a swellable polymer, a non-swellable polymer, aporous polymer, a non-porous polymer, an erodible polymer (such as adissolvable polymer), a pH-sensitive polymer, a natural polymer, awax-like material, and a combination thereof. In some embodiments, thethermoplastic material is one of or a combination of the following:cellulose ether, cellulose ester, acrylic resin, ethyl cellulose,hydroxylpropyl methyl cellulose, hydroxylpropyl cellulose, hydroxylmethyl cellulose, mono- or diglyceride of C₁₂-C₃₀ fatty acid, C₁₂-C₃₀fatty alcohol, wax, poly(meth) acrylic acid, polyvinylcaprolactam-polyvinyl acetate-polyethylene glycol graft copolymer57/30/13, polyvinylpyrrolidone-vinyl acetate copolymer (PVP-VA),polyvinylpyrrolidone-vinyl acetate copolymer (PVP-VA) 60/40,polyvinylpyrrolidone (PVP), polyvinyl acetate (PVAc),polyvinylpyrrolidone (PVP) 80/20, vinylpyrrolidone-vinyl acetatecopolymer (VA64), polyethylene glycol-polyvinyl alcohol graft copolymer25/75, kollicoat IR-polyving alcohol 60/40, polyvinyl alcohol (PVA orPV-OH), poly(vinyl acetate) (PVAc), butylmethacrylate-(2-dimethylaminoethyl) methacrylate-methyl methacrylatecopolymer 1:2:1, dimethylaminoethyl methacrylate-co-methacrylic esterm,ethyl acrylate-methyl methacrylate-trimethylammonium ethyl methacrylatechloride copolymer, methyl acrylate-methyl methacrylate-methacrylic acidcopolymer 7:3:1, methacrylic acid-methyl methacrylate copolymer 1:2,methacrylic acid-ethyl acrylate copolymer 1:1, polyethylene oxide (PEO),polyethylene glycol (PEG), hyperbranched polyesteramide, hydroxypropylmethyl cellulose phthalate, hypromellose phthalate, hydroxypropyl methylcellulose or hypromellose (HMPC), hydroxypropyl methylcellulose acetatesuccinate or hypromellose acetate succinate (HPMCAS),poly(lactide-co-glycolide) (PLGA), carbomer, ethylene-vinyl acetatecopolymer, polyethylene (PE) and polycaprolactone (PCL), hydroxyl propylcellulose (HPC), polyoxyethylene 40 hydrogenated castor oil, methylcellulose (MC), ethyl cellulose (EC), poloxamer, hydroxypropyl methylcellulose phthalate (HPMCP), poloxamer, hydrogenated castor oil,hydrogenated soybean oil, glyceryl palmitostearate, Brazilian palm wax,polylactic acid (PLA), polyglycolic acid (PGA), cellulose acetatebutyrate (CAB), polyvinyl acetate phthalate (PVAP), wax, beeswax,hydrogel, gelatin, hydrogenated vegetable oil, polyvinyl acetal diethylaminolactate (AEA), paraffin, shellac, sodium alginate, celluloseacetate phthalate (CAP), Arabic gum, xanthan gum, glycerol monostearate,octadecanoic acid, thermoplastic starch, and derivatives thereof (forexample, the salts, amides, or esters thereof).

In some embodiments, the erodible material includes a non-thermoplasticmaterial. In some embodiments, the erodible material is anon-thermoplastic material. In some embodiments, the non-thermoplasticmaterial is non-thermoplastic starch, sodium starch glycoacetate(CMS-Na), sucrose, dextrin, lactose, microcrystalline cellulose (MCC),mannitol, magnesium stearate (MS), powdered silica gel, glycerol, syrup,lecithin, soybean oil, tea oil, ethanol, propylene glycol, glycerol,Tween, animal fat, silicone oil, cocoa butter, fatty acid glyceride,vaseline, chitosan, cetyl alcohol, stearyl alcohol, polymethacrylate,non-toxic polyvinyl chloride, polyethylene, ethylene-vinyl acetatecopolymer, silicone rubber, or a combination thereof.

Exemplary materials that may be used with the device described herein orthe methods described herein include, but are not limited to: poly(methyl) acrylate copolymer (such as a copolymer containing one or moreof amino alkyl methacrylic acid, methacrylic acid, methacrylic esterand/or ammonium alkyl methacrylate, such as a copolymer sold under thebrand name Eudragit® RSPO) and hydroxyl propyl cellulose (HPC).

In some embodiments, the material includes a drug. In some embodiments,the material is admixed with a drug.

The material can be pressurized in the printing module by using apressure regulating apparatus. The material is preloaded into a barrel,and a pressure regulating apparatus (not shown FIG. 1) can apply apressure to the material preloaded in the barrel 133. The pressureregulating apparatus may be a motor (for example, a stepper motor), avalve, or any other suitable control device that drives a mechanism, forexample, a piston, a pressure screw, or compressed air (i.e. a pneumaticcontroller), to apply a pressure to the material contained within thebarrel. The barrel includes one or more heaters that can melt thematerial. In some embodiments, the heater is disposed in the barrel. Insome embodiments, the heater is disposed on the flank of the barrel orsurrounding the barrel. In some embodiments, the heater is an electricradiant heater, for example, an electric heating tube or coil. Theheater of the barrel is preferably a high-efficiency heater with a highvoltage and high output power. In some embodiments, the heater of thebarrel has a rated voltage between 110 V and 600 V. In some embodiments,the heater of the barrel has a rated voltage between 210 V and 240 V. Insome embodiments, the heater of the barrel is a 220 V heater. In someembodiments, the heater of the barrel has output power between about 30W and about 100 W, for example, between 40 W and 80 W, or about 60 W. Insome embodiments, the heater is an electric heating coil that surroundsthe outside of the barrel. Preferably, the barrel is made of aheat-resistant material, such as stainless steel (for example, 316Lstainless steel). In some embodiments, the device includes one or moretemperature sensors. The one or more temperature sensors are positionedproximal to the feed channel or inside the feed channel. The temperaturesensor is configured to measure the temperature of the material withinthe feed channel. The feed channel is relatively wide, when comparedwith the extrusion port of the nozzle. In some embodiments, the feedchannel has a diameter between about 1 mm and about 15 mm, for example,between about 1 mm and about 5 mm, between about 5 mm and about 10 mm,or between about 10 mm and about 15 mm. In an exemplary embodiment, thefeed channel has a diameter of about 8 mm.

A printing head of the device includes a nozzle 131. The nozzle includesan extrusion port through which a melted material is extruded. Theextrusion port is located at the distal end of the nozzle relative tothe feed channel. When the sealing needle is in the open position, themelted material flows out of the extrusion port from the feed channelthrough the nozzle. The nozzle includes a tapered inner surface, withthe extrusion port close to the vertex of the tapered inner surface. Insome embodiments, the inner surface of the nozzle includes a pad or aliner. The pad or the liner can be made of polytetrafluoroethylene(PTFE) or any other suitable material. In some embodiments, the printinghead includes one or more heaters, which may be located inside,surrounding, or proximal to the nozzle of the printing head. The one ormore heaters are configured to heat the material within the nozzle. Thematerial may have a temperature that is the same as or different fromthe temperature of the material in the barrel or in the feed channel. Insome embodiments, a heater of the nozzle is an electric radiant heater,for example, an electric heating tube or coil. The heater may be alower-voltage and/or lower-power heater than a heater of the barrel or aheater of the feed channel. In some embodiments, the heater of thenozzle has a rated voltage between 6 V and 60 V. In some embodiments,the heater of the nozzle is a 12 V heater. In some embodiments, theheater of the nozzle has output power between about 10 W and about 60 W,for example, between 20 W and 45 W, or about 30 W.

In some embodiments, the device includes one or more temperaturesensors. In some embodiments, the printing head includes one or moretemperature sensors positioned proximal to or inside the nozzle, tomeasure the temperature of the material within the nozzle. In someembodiments, the device includes a temperature sensor located inside orproximal to a material pipe, or a temperature sensor configured tomeasure a temperature inside the material pipe. In some embodiments, thedevice includes a temperature sensor located inside or proximal to thefeed channel, or a temperature sensor configured to measure atemperature inside the feed channel. In some embodiments, the deviceincludes a temperature sensor located inside or proximal to the printinghead, or a temperature sensor configured to measure a temperature insidethe nozzle. In some embodiments, the one or more temperature sensors areconnected to a computer system that operates the one or more heaters inresponse to a temperature reported by the one or more temperaturesensors. For example, the computer system can operate the one or moreheaters to regulate the temperature of the material within the barrel,the feed channel, and/or the nozzle. In some embodiments, the systemoperates as a closed-loop feedback system to maintain an approximatelyconstant temperature inside the device or inside a component of thedevice (i.e. the barrel, the nozzle, or the feed channel). Thetemperatures of materials within different components of the device maybe the same or different. In some embodiments, the feedback system isoperated by using a proportional-integral-derivative (PID) controller, abang-bang controller, a predictive controller, a fuzzy control system,an expert system controller, or any other suitable algorithm.

The device includes one or more pressure sensors 106, which can measurethe pressure of the material within the device. In some embodiments, thepressure sensor is configured to measure the pressure of the materialwithin the printing head or within the feed channel close to theprinting head. In some embodiments, the pressure sensor is disposed inthe printing head, or disposed at a position adjacent to the feedchannel and close to the printing head. In some embodiments, thepressure sensor may work together with a pressure regulating apparatusof a closed-loop feedback system, to provide the material within thedevice with an approximately constant pressure. For example, when thepressure sensor measures that the pressure drops, the feedback systemmay send a signal to the pressure regulating apparatus, so as toincrease the pressure of the material (for example, by lowering apiston, increasing an air pressure inside the barrel, or turning apressure screw). Similarly, when the pressure sensor measures that thepressure rises, the feedback system may send a signal to the pressureregulating apparatus, so as to reduce the pressure of the material (forexample, by raising the piston, decreasing the air pressure inside thebarrel, or turning the pressure screw). The constant pressure ensuresthat the melted material within the device passes through the extrusionport of the nozzle at a constant rate when the sealing needle is in theopen position. However, when the sealing needle is in the closedposition, an increase in the constant temperature (for example, byraising the piston, decreasing the air pressure inside the barrel, orturning the pressure screw) may cause the melted material to leakthrough the nozzle. In addition, when the sealing needle switches backfrom the open position to the closed position or switches back from theclosed position to the open position, the feedback system that includesthe pressure sensor and the pressure regulating apparatus will maintainan approximately constant pressure inside the system. When the sealingneedle switches from the closed position to the open position, a ramp-upof the extrusion rate is minimized, because the pressure of the materialwithin the system does not need to be increased. In some embodiments,the pressure sensor 106 is connected to a computer system that operatesthe barrel to pressurize the material to a desired pressure in responseto the pressure reported by the pressure sensor 106. For example, thecomputer system can operate the pressure regulating apparatus toregulate an amount of pressure exerted on the material within thebarrel. In some embodiments, the system operates as a closed-loopfeedback system to maintain an approximately constant pressure insidethe device. In some embodiments, the feedback system is operated byusing a proportional-integral-derivative (PID) controller, a bang-bangcontroller, a predictive controller, a fuzzy control system, an expertsystem controller, or any other suitable algorithm. In some embodiments,the pressure sensor is precise within 0.005 MPa, within 0.008 MPa,within 0.05 MPa, within 0.1 MPa, within 0.2 MPa, within 0.5 MPa, orwithin 1 MPa. In some embodiments, a sampling time of the pressuresensor is about 20 ms or less, for example, about 10 ms or less, about 5ms or less, or about 2 ms or less. In some embodiments, the pressure ofthe material is within about 0.005 MPa, about 0.008 MPa, about 0.05 MPa,about 0.1 MPa, about 0.2 MPa, about 0.5 MPa, or about 1 MPa of thedesired pressure.

The device includes a control switch 108. The control switch 108 can beoperated to prevent or allow the melted material to flow from theextrusion port of the device. The control switch 108 includes a sealingneedle operable between an open position and a closed position, wherethe material is inhibited from flowing through the nozzle 131 when thesealing needle is in the closed position. The sealing needle extendsthrough at least a portion of the feed channel and includes a taperedend. When the sealing needle is in the closed position, the tapered endof the sealing needle engages with the tapered inner surface of thenozzle 131 (for example, at the extrusion port of the nozzle).

In some embodiments, any portion of the sealing needle that contacts thematerial is free of protrusions. A protrusion can be any portion of thesealing needle that has a diameter larger than a shaft of the sealingneedle, or any portion of the sealing needle that extends outwardfurther than the shaft of the sealing needle. A protrusion on thesealing needle can push the melted material to pass through theextrusion port when the sealing needle is in the closed position, and ispreferably avoided. In some embodiments, the entire sealing needle(regardless of whether the sealing needle contacts the material or not)is free of protrusions. In some embodiments, a portion of the sealingneedle that does not contact the material includes one or moreprotrusions, which may, for example, engage with a component of theactuator or act as a depth break to prevent the sealing needle frombeing driven too far within a feed chamber.

The portion of the sealing needle that contacts the material (i.e. theportion located in the feed channel when the sealing needle is in theopen position or the closed position) is relatively thin compared withthe feed channel, and allows the melted material to flow around thesealing needle rather than being pushed out of the extrusion port. Insome embodiments, the portion of the sealing needle that contacts thematerial has a largest diameter of about 0.2 mm to 3.0 mm, for example,about 0.2 mm to 0.5 mm, about 0.5 mm to 1.0 mm, about 1.0 mm to 1.5 mm,about 1.5 mm to 2.0 mm, about 2.0 mm to 2.5 mm, or about 2.5 mm to 3.0mm. In some embodiments, the sealing needle (including the portion ofthe sealing needle that contacts the material and the portion of thesealing needle that does not contact the material) has a largestdiameter of about 0.2 mm to 3.0 mm, for example, about 0.2 mm to 0.5 mm,about 0.5 mm to 1.0 mm, about 1.0 mm to 1.5 mm, about 1.5 mm to 2.0 mm,about 2.0 mm to 2.5 mm, or about 2.5 mm to 3.0 mm.

In some embodiments, the sealing needle includes a pointed tip at thetapered end, as shown in FIG. 10A. In some embodiments, the tapered endof the tip is frustoconical, as shown in FIG. 10B. Both the nozzle andthe sealing needle include tapered surfaces so that the tapered end ofthe sealing needle faces the tapered inner surface of the nozzle. The“taper angle” herein refers to the angle of the vertex of a joiningsurface. In the instance of a frustoconical tapered tip, the “taperangle” refers to the vertex of an extrapolated joining surface. Thetaper angle of the tapered end of the sealing needle is indicated by ain FIG. 10A and FIG. 10B. As shown in FIG. 10C, the taper angle of thenozzle is indicated by β. In some embodiments, the taper angle of thetapered end of the sealing needle is about 60° or less, for example,about 50° or less, about 45° or less, about 40° or less, about 35° orless, about 30° or less, about 25° or less, about 20° or less, or about15° or less. In some embodiments, the taper angle (α) of the sealingneedle is equal to or less than the taper angle (β) of the inner surfaceof the nozzle. In some embodiments, a ratio of the taper angle (β) ofthe inner surface of the nozzle to the taper angle (α) of the sealingneedle is about 1:1 to about 4:1, or about 1:1 to about 3:1, or about1:1 to about 2:1.

The sealing needle is positioned in the closed position by lowering thesealing needle towards the extrusion port, and in this case the sealingneedle is aligned with the extrusion port. When the sealing needle is inthe open position, the pressurized and melted material can flow throughthe extrusion port. When the sealing needle is in the closed position,however, the pressurized and melted material is prevented from flowing,where the sealing needle engages with the inner surface of the nozzle.When the taper angle (β) of the inner surface of the nozzle is largerthan the taper angle (α) of the sealing needle, the tapered end of thesealing needle engages with the inner surface of the nozzle at theextrusion port. In some embodiments, the extrusion port has a diameterof about 0.1 mm or more, for example, about 0.15 mm or more, about 0.25mm or more, about 0.5 mm or more, or about 0.75 mm or more. In someembodiments, the extrusion port has a diameter of about 1 mm or less,for example, about 0.75 mm or less, about 0.5 mm or less, about 0.25 mmor less, or about 0.15 mm or less. The base of the tapered end of thesealing needle is preferably thin to inhibit the melted material frombeing pushed to pass through the extrusion port when the sealing needleis in the closed position. In some embodiments, a ratio of the largestdiameter of the tapered end of the sealing needle (i.e. the base of thetaper) to the diameter of the extrusion port is about 1:0.8 to about1:0.1, for example, about 1:0.8 to about 1:0.7, about 1:0.7 to about1:0.6, about 1:0.6 to about 1:0.5, about 1:0.5 to about 1:0.4, about1:0.4 to about 1:0.3, about 1:0.3 to about 1:0.2, or about 1:0.2 toabout 1:0.1.

The sealing needle preferably includes a strong yet flexible material.Exemplary materials include but are not limited to stainless steel,polytetrafluoroethylene (PTFE) and carbon fiber. In some embodiments,the inner surface of the nozzle includes a flexible pad or liner, whichcan inhibit damage to the needle or nozzle upon repeated repositioningof the sealing needle in the open position or closed position. In someembodiments, the pad or liner is made of polytetrafluoroethylene (PTFE).

The sealing needle of the control switch is controlled by using anactuator that can position the sealing needle in an open position (i.e.by raising the sealing needle so that the tapered end of the sealingneedle no longer engages with the inner surface of the nozzle) or aclosed position (i.e. by lowering the sealing needle so that the taperedend of the sealing needle engages with the inner surface of the nozzle).In some embodiments, the actuator is a pneumatic actuator, and can becontrolled by using air pressure inside the actuator. In someembodiments, the actuator is a mechanical actuator, which can raise orlower the sealing needle through the use of one or more gears and amotor. In some embodiments, the actuator includes a solenoid valve or anelectrostrictive polymer.

FIG. 9B illustrates a cross-sectional view of an exemplary device fordepositing a material by additive manufacturing according to the presentinvention. A material can be loaded onto a barrel 902, and a piston 904applies a pressure to the material by pushing into the barrel 902. Thepiston 904 is connected to a pressure regulating apparatus through aguide arm 906. The piston 904 is lowered by a motor, such as a steppermotor, to increase the pressure of the material in the barrel 902, or israised to lower the pressure of the material. The material in the barrel902 can be heated to or above a melting temperature of the material byusing a heater inside or surrounding the barrel 902. The melted materialfrom the barrel 902 flows through a feed channel 908, where the feedchannel 908 is connected to a printing head 910 that includes a nozzle912. A pressure sensor 914 is located at the end of the feed channel908, and close to the printing head 910, and is configured to measurethe pressure of the material close to the printing head. In someembodiments, the pressure sensor 914 is positioned to measure thepressure of the material within the printing head 910. The pressuresensor 914 can transmit the measured pressure to a computer system,where the computer system can operate the pressure regulating apparatus(or a motor of the pressure regulating apparatus) to reposition thepiston 904 and control the pressure of the material within the barrel902. This can be operated in a feedback system, where the change of thepressure is then measured by the pressure sensor 914, and the computersystem further operates the pressure regulating apparatus.

The device includes a control switch 916, and the control switch 916includes a sealing needle 918 and a linear actuator 920. The sealingneedle 918 includes an upper end 922 that engages with the actuator 920,and a lower end 924 that is tapered. The sealing needle 918 extendsthrough the feed channel 908 into the printing head 910. The actuator920 operates the sealing needle 918 between an open position (raised)and a closed position (lowered). When the sealing needle 918 is in theclosed position, the tapered end 924 of the sealing needle 918 engageswith a tapered inner surface of the nozzle 912 to inhibit flowing of themelted material through the nozzle. To open the nozzle 912 and allow themelted material to flow through an extrusion port, the actuator 920operates the sealing needle 918 to position the sealing needle 918 inthe open position by raising the sealing needle 918, so that the taperedlower end 924 is disengaged from the inner surface of the nozzle 912.

FIG. 9C illustrates an enlarged view of the printing head 910 when thesealing needle 918 is in the closed position and engages with the nozzle912. In the closed position, the tapered end 924 of the sealing needle918 is inserted into an extrusion port 926 by engaging with the taperedinner surface of the nozzle 912. The melted material in the feed channel908 is therefore prevented from flowing through the extrusion port 926.The pressure of the material within or proximal to the printing head 910is measured by the pressure sensor 914, and the pressure regulatingapparatus can be operated to prevent excess pressure buildup in thedevice when the sealing needle 918 is in the closed position.

The sealing needle 918 extends through the feed channel 908 into theprinting head 910. When the sealing needle 918 switches from the openposition to the closed position, a careful design prevents the meltedmaterial in the feed channel 908 from being pushed out of the extrusionport 926. The tapered end 924 of the sealing needle 918 allows thesealing needle 918 to pierce the melted material, allowing the meltedmaterial to flow upward and around the enclosed sealing needle 918instead of being pushed down.

The pneumatic actuator 920 includes a solenoid valve, configured tocontrol the flow of gas into an air chamber 926. The air chamber candrive up or down a central rod 928 attached to the upper end 922 of thesealing needle 918. High-pressure gas flows into the air chamber 926from a position below a diaphragm 930, or gas is removed from a positionabove the diaphragm 930, so that the diaphragm 930 moves upward, therebypositioning the sealing needle 918 in the open position. The gas isremoved from a position below the diaphragm 930, or the high-pressuregas is applied above the diaphragm 930, so that the diaphragm 930 movesdownward, thereby positioning the sealing needle 918 in the closedposition.

FIG. 9D illustrates an exploded view of components of a pneumaticactuator that is connected to a sealing needle to control the sealingneedle. A diaphragm 942 is located in an air chamber of the pneumaticactuator, and is connected to a central rod 974, for example, through athreaded fit. The central rod 974 is connected to an adapter 976, forexample, through a threaded fit. The adapter 976 is attached to asealing needle 978, for example, through a threaded fit or through aforce fit. For example, a lower part of the adapter 976 may include anopening, and an upper part of the sealing needle 978 can be snugly fitinto the opening by jamming the sealing needle 978 into the opening ofthe adapter 976. The sealing needle 978 passes through a gasket 980,where the gasket 980 is held in place by a fixing nut 982. The fixingnut 982 is attached to the rest of the device through a manifold block,which holds the fixing nut 982 and the gasket in place. As shown in FIG.9B, a manifold block 932 is positioned above the feed channel 908, andis aligned with the nozzle 912 of the printing head 910. A manifoldblock channel 934 passes through the manifold block 932 to enter thefeed channel. The gasket 936 fits into an opening on the top of themanifold block 932, where the opening is wider than the channel 934,thereby preventing the gasket 936 from moving toward the printing head910. The gasket 936 may be made of an inert pliable material, such asplastic or synthetic rubber, and seals the feed channel 908 to preventleakage of the melted material. In some embodiments, the gasket is madeof polytetrafluoroethylene (PTFE). A fixing nut 938 is secured to themanifold block 932, for example, through a threaded fit, and secures thegasket 936. Accordingly, the gasket 936 is in a fixed position relativeto the printing head 910 and the nozzle 912. The sealing needle 918passes through a hole in the fixing nut 938 and the gasket 936 to reachthe feed channel 908. The hole is sized to allow the needle to passthrough and move as controlled by the actuator 916, but is not so largeas to allow leakage of the melted material.

The printing module includes one or more heaters configured to melt amaterial. The heater can be placed around or inside a barrel thatcontains the material, the feed channel and/or the printing head. FIG.13A shows a longitudinal section view of a portion of the device, withFIG. 13B showing a cross-sectional view of the apparatus at a plane“A-A”, and FIG. 13C showing a non-cross sectional view of the device. Insome embodiments, the device includes a heater 1302 surrounding a barrel1304 of the device. The heater 1302 can heat and melt a materialcontained within the barrel 1304. The heater 1302 may be, for example, acoil heater that surrounds the outside of the barrel 1304. In someembodiments, the heater is disposed in the barrel. The material placedwithin the barrel is initially melted in the barrel by the heater, and apressure is applied to the material by a piston 1306. Then the meltedmaterial flows from the barrel 1304 to a feed channel 1308. In someembodiments, to ensure that the material in the feed channel 1308remains a desired temperature, one or more heaters can be disposedproximal to or inside the feed channel 1308. FIG. 13B and FIG. 13Cillustrate two heaters 1310 a and 1310 b, which are located on two sidesof the feed channel 1308 and adjacent to the feed channel 1308. In someembodiments, the heater 1310 a or the heater 1310 b or both span thelength of the feed channel 1308, or span the length of the flank of thefeed channel 1308. In some embodiments, the one or more heaters adjacentto or inside the feed channel 1308 are a heating rod. In someembodiments, the one or more heaters adjacent to or inside the feedchannel 1308 are a coil that surrounds the feed channel 1308. The one ormore heaters for heating within the feed channel 1308 ensure that thematerial remains melted and has a proper viscosity under a given appliedpressure, to implement predictable flowing. In some embodiments, aprinting head 1312 of the device includes one or more heaters 1314,which ensure that the material remains melted and has a proper viscosityinside a nozzle 1316.

In some embodiments, the device includes one or more temperaturesensors, which may be located at one or more positions inside the deviceand can measure the temperature of the material within the device, forexample, within the barrel, within the feed channel, or within theprinting head. The embodiments illustrated in FIG. 13A to FIG. 13Cinclude a first temperature sensor 1318 adjacent to the feed channel1308, and a second temperature sensor 1320 adjacent to the printing head1312. In the figures, the temperature sensor 1318 adjacent to the feedchannel 1308 is on one side of the feed channel 1308, but thetemperature sensor 1318 may optionally be located anywhere along thelength of the feed channel 1308. The temperature sensor 1318 and the oneor more heaters (for example, 1310 a and 1310 b) may serve as aclosed-loop feedback system for the material melted in the feed channel1308, where the feedback system can ensure that the material within thefeed channel remains an approximately constant temperature. For example,the temperature sensor 1318 can transmit a measured temperature to acomputer system, and the computer system can operate the one or moreheaters 1310 a and 1310 b to ensure an approximately constanttemperature. The temperature sensor 1320 in the printing head 1312 ofthe device can operate with the one or more heaters 1314 in the printinghead in a closed-loop feedback system, to ensure an approximatelyconstant temperature of the material within the printing head. Thefeedback system can be operated by using aproportional-integral-derivative (PID) controller, a bang-bangcontroller, a predictive controller, a fuzzy control system, an expertsystem controller, or any other suitable algorithm. In some embodiments,the one or more heaters in the device heat the material within thesystem to a temperature equal to or above the melting temperature of thematerial. In some embodiments, the one or more heaters heat the materialto a temperature of about 60° C. or higher, for example, about 70° C. orhigher, about 80° C. or higher, about 100° C. or higher, about 120° C.or higher, about 150° C. or higher, about 200° C. or higher, or about250° C. or higher. In some embodiments, the one or more heaters heat thematerial to a temperature of about 300° C. or lower, for example, about260° C. or lower, about 200° C. or lower, about 150° C. or lower, about100° C. or lower, or about 80° C. or lower. In some embodiments, the oneor more heaters heat the material to different temperatures at differentpositions of the device. For example, in some embodiments, the materialis heated to a first temperature inside the barrel, a second temperatureinside the feed channel, and a third temperature inside the printinghead, where the temperatures may be same temperatures or differenttemperatures. By way of example, a material may be heated to 140° C.inside the barrel and the feed channel, but to 160° C. inside theprinting head. The feedback control system allows high-precisiontemperature control. In some embodiments, the temperature is controlledwithin 0.1° C. of a target temperature, within 0.2° C. of the targettemperature, within 0.5° C. of the target temperature, or within 1° C.of the target temperature.

FIG. 11 illustrates another example of the device according to thepresent invention. A material is loaded into a barrel 1102 of a printingmodule, and a pressure screw (or piston) 1104 can apply a pressure tothe material in the barrel 1102. To increase the pressure on thematerial, a pressure controller 1106 (for example, a stepper motor)turns a first gear 1108, and the first gear 1108 turns a second gear1110 connected to the pressure screw 1104. The material in the barrel1102 can be heated by a heater 1114 surrounding the barrel 1102. Amelted material from inside the barrel 1102 flows through a feed channel1116 to a printing head 1118 that includes a nozzle 1120. The device mayinclude a pressure sensor 1130, where the pressure sensor 1130 isconfigured to measure the pressure of the material in the barrel 1102,the feed channel 1116, and/or the printing head 1118. The pressuresensor 1130 can transmit the measured pressure to a computer system,where the computer system can operate the pressure controller 1108 toreposition the pressure screw 1104 and control the pressure of thematerial within the barrel 1102. This can be operated in a feedbacksystem, where the change of the pressure is then measured by thepressure sensor 1130, and the computer system further operates thepressure controller. The device illustrated in FIG. 11 includes acontrol switch. The control switch includes a sealing needle 1122 alongthe same axis as the barrel 1102, and an actuator 1124. The sealingneedle 1122 includes an upper end that is connected to the actuator1124, and a lower tapered end (not shown). The actuator 1124 operatesthe sealing needle 1122 between an open position (raised) and a closedposition (lowered). When the sealing needle 1122 is in the closedposition, the tapered end 1122 of the sealing needle 1122 engages with atapered inner surface of the nozzle 1120 to inhibit flowing of themelted material through the nozzle. The printing head 1118 may furtherinclude one or more heaters 1126 and a temperature sensor 1128, whichcan be operated in a feedback system.

In some embodiments, there is an additive manufacturing system thatincludes a plurality (for example, two or more, three or more, four ormore, five or more, or six or more) of devices according to the presentinvention. The devices each include a printing module equipped with acontrol switch (including a sealing needle with a tapered end operablein an open position and a closed position, and a nozzle). Materials inthe independent devices may be the same or different. For example, insome embodiments, the system includes two devices and two differentmaterials (i.e. a first material and a second material). In someembodiments, the system includes three devices and three differentmaterials (i.e. a first material, a second material, and a thirdmaterial). In some embodiments, the system includes four devices andfour different materials (i.e. a first material, a second material, athird material, and a fourth material). In some embodiments, the systemincludes five devices and five different materials (i.e. a firstmaterial, a second material, a third material, a fourth material, and afifth material). In some embodiments, the system includes six devicesand six different materials (i.e. a first material, a second material, athird material, a fourth material, a fifth material, and a sixthmaterial). In some embodiments, the additive manufacturing systemincludes a first device loaded with a first material and a second deviceloaded with a second material, where the first material is differentfrom the second material. The different printing modules in the 3Dprinting system can extrude different materials to form amulti-component printed product, for example, a multi-componentpharmaceutical dosage form (such as a pharmaceutical tablet). When oneof the printing modules is active (i.e. the sealing needle is in theopen position), the other printing modules in the device are inactive(i.e. the sealing needle is in the closed position). The device canquickly switch between active printing modules by coordinating theposition of the sealing needle in either the open position or the closedposition. FIG. 12 illustrates a portion of an exemplary system thatincludes three printing modules, each with a distinct printing head1202, 1204, or 1206. A printing table 1208 is movable on an X-axis, aY-axis, and a Z axis. A material can be extruded from a correct printinghead to manufacture a product 1210 (such as a pharmaceutical tablet).

FIG. 3 illustrates a schematic diagram of a 3D printing device accordingto a particular embodiment of the present invention.

As shown in FIG. 3, a 3D printing device 300 further includes a controlmodule 505. The control module 505 may be composed of one or more PLCcontrollers, a single-chip microcomputer, or an electronic computer, andhas a computerized user interface. The control module 505 iscommunicatively connected to a feeding module 501, a melt extrusionmodule 502, a printing module 503, a platform module 504, a temporarystorage module 507, and a mixing module 508 of the 3D printing device300; and controls specific operation of each module according to astatus parameter. The status parameter may include but is not limitedto: a numerical model of a product, a melting point of an initialmaterial, a pressure at a nozzle, a quantity of products required, aquantity of products actually obtained, a required composition of theproduct, required weight of the product, required moisture of theproduct, and a required quantity of colonies of the product. Theseparameters may be stored in a digital storage apparatus of an electroniccomputer of the control module 505, or may be input or selected by auser on a computerized user interface.

In some embodiments, the 3D printing device 300 further includes aplurality of measurement apparatuses disposed in the foregoing modules,configured to obtain, in real time, some specific status parametersmonitored at the foregoing modules. The specific status parameter mayinclude the temperature, composition, pressure, weight, moisture, andshape of a melt. In some embodiments, the specific status parameter maybe the weight, shape, moisture, and heating temperature of an initialmaterial, and the like. In some embodiments, the specific statusparameter may be the composition, pressure, weight, moisture, and shapeof a product needing to be printed, and the like. Correspondingly, themeasurement apparatuses included in the 3D printing device 300 may be atemperature sensor, a composition sensor, a pressure sensor, a weightsensor, a moisture sensor, and the like.

In some embodiments, the composition sensor may be a near-infraredspectrum analyzer. The near-infrared spectrum analyzer has a probe thatcan be inserted into a to-be-measured object. The near-infrared spectrumanalyzer can obtain specific amounts of various components of asubstance through the probe. The near-infrared spectrum analyzer ismainly configured to measure a composition of fluid such as a melt. Insome embodiments, the near-infrared spectrum analyzer may further have aprobe for measuring a composition of a powdered substance, where theprobe can be inserted into an initial material to measure an amount andmoisture of a powdered material, and the like. Therefore, in someembodiments, the disposed moisture sensor may alternatively be anear-infrared spectrum analyzer.

In some embodiments, the measurement apparatuses of the 3D printingdevice 100 shown in FIG. 1 may further include a camera and anotherimaging apparatus. The camera or imaging apparatus may be configured tomeasure the feeding module 101, so as to measure, in real time, aparameter such as the shape and size of the initial material that is fedby the feeding module to the melt extrusion module 102, and thedischarge speed of the initial material at the discharge outlet 113. Thecamera or imaging apparatus may be disposed below the feeding module 101or at the discharge outlet 113. In some embodiments, the camera orimaging apparatus may be further configured to measure the printingmodule 103 or the platform module 104, and is specifically configured toperform real-time image sensing of a status parameter about a dischargestatus of the nozzle 131, such as a discharge speed and continuity ofdischarge; and a status parameter of a product deposited on thedeposition platform 141 of the platform module 104, such as a shape, asize, and a curing speed. The camera or imaging apparatus may bedisposed on the printing module 103 or the platform module 104, ordisposed between the printing module 103 and the platform module 104.Specifically, in some embodiments, the camera or imaging apparatus maybe disposed at a position aligned with the nozzle 131, with a planemirror further disposed at the nozzle 131, where a certain angle existsbetween a plane on which the plane mirror is located and a plane onwhich the deposition platform 141 is located, thereby reflecting a lightray that is reflected by the deposition platform 141 to the camera orimaging apparatus. Such arrangement of the camera or imaging apparatuscan satisfy a requirement for measuring the foregoing specific statusparameter both at the nozzle 131 and at the deposition platform 141.

In some embodiments, a first temperature sensor (not shown in FIG. 3),which is communicatively connected to the control module 505, isdisposed in a processing chamber of the melt extrusion module, and isconfigured to measure the temperature of a melt in the processingchamber of the melt extrusion module 502 and transmit a firsttemperature measurement signal to the control module 505. The controlmodule 505 determines the temperature of the melt in the processingchamber of the melt extrusion module 502 according to the firsttemperature measurement signal, and judges whether the temperature iswithin a first desired temperature range. The temperature of the melt inthe processing chamber of the melt extrusion module 502 should beslightly higher than the melting point of the initial material, so as toensure that the initial material in the processing chamber issufficiently melted. During practical operation, there is a specificrelationship between the first desired temperature range and thestructure and composition of a product needing to be printed, andbetween the first desired temperature range and the type of initialmaterial. Whether the temperature of the melt in the melt extrusionmodule 502 is within the desired range directly determines viscousfluidity, adhesive properties, and the like of the melt during aprinting process, thereby affecting continuity and precision of 3Dprinting. The control module 505 may determine the first desiredtemperature range according to the product needing to be printed, oraccording to a status parameter input by a user on a user interface.

In some embodiments, when the first temperature measurement signalindicates that the temperature of the melt in the processing chamber ofthe melt extrusion module 502 is lower than the first desiredtemperature range, the control module 505 may raise heating power of oneor more processing chamber heating apparatuses that are disposed in themelt extrusion module 502 for the melt. It should be noted that, becausethe melt extrusion module 502 generates internal heat during the processof extruding and shearing the initial material, in some embodiments, thecontrol module 505 may alternatively regulate the temperature of themelt in the processing chamber of the melt extrusion module 502 bycontrolling the extrusion power of the melt extrusion module 502according to the first temperature measurement signal. On the contrary,when the first temperature measurement signal indicates that thetemperature of the melt in the processing chamber is higher than thefirst desired temperature range, the control module 505 performs reverseoperation to stop heating of the one or more processing chamber heatingapparatuses that are disposed in the melt extrusion module 502 or reducetheir heating power.

In some embodiments, a second temperature sensor (not shown in FIG. 3)is further disposed in the printing module 503, and is configured tomeasure the temperature of a melt in the printing module and transmit asecond temperature measurement signal to the control module 505. Thecontrol module 505 controls the temperature of the melt in the printingmodule 503 within a second desired temperature range according to thesecond temperature measurement signal. The temperature of the melt inthe printing module 503 is of great importance to accuracy andcontinuity of forming of an ultimate printed product, and is generallyset to a value higher than the melting point of the melt. Same as thefirst desired temperature range, the second desired temperature range isrelated to the structure and composition of the product needing to beprinted, the type of initial material, and the like. The control module505 may determine the second desired temperature range according to theproduct needing to be printed, or according to a status parameter inputby a user on a user interface.

In some embodiments, when the second temperature measurement signalindicates that the temperature of the melt in the printing module 503 islower than the second desired temperature range, the control module 505may raise heating power of a temperature regulating apparatus (not shownFIG. 3) of the printing module 503 for the melt. For details aboutarrangement and structure of the temperature regulating apparatus, referto the temperature regulating apparatus 134 of the printing module ofthe foregoing 3D printing device. When the second temperaturemeasurement signal indicates that the temperature of the melt in theprinting module 503 is higher than the second desired temperature range,the control module 505 performs reverse operation to stop thetemperature regulating apparatus of the printing module 503 for heatingthe melt or reduce the heating power of the temperature regulatingapparatus. In some embodiments, the temperature of the melt in theprinting module 503 can be reduced through the temperature regulatingapparatus, so that the temperature of the melt in the printing module503 remains slightly higher than the melting point of the initialmaterial, to obtain a better product printing effect.

In some embodiments, a third temperature sensor (not shown FIG. 3) isfurther disposed in the storage chamber of the temporary storage module507, and is configured to measure the temperature of a melt in a storagechamber of the temporary storage module 507 and transmit a thirdtemperature measurement signal to the control module 505. The controlmodule 505 controls the temperature of the melt in the storage chamberof the temporary storage module 507 within a third desired temperaturerange according to the third temperature measurement signal. Thetemperature of the melt in the storage chamber of the temporary storagemodule 507 should be slightly higher than the melting point of the melt,so as to maintain a melted status of the initial material in the storagechamber. Same as the first desired temperature range, the third desiredtemperature range is related to the structure and composition of theproduct needing to be printed, the type of initial material, and thelike. The control module 505 may determine the third desired temperaturerange according to the product needing to be printed, or according to astatus parameter input by a user on a user interface.

In some embodiments, when the third temperature measurement signalindicates that the temperature of the melt in the storage chamber islower than the third desired temperature range, the control module 505may raise heating power of a storage chamber heating apparatus (notshown FIG. 3) disposed in the storage chamber of the temporary storagemodule 507 for the melt. The storage chamber heating apparatus disposedin the storage chamber of the temporary storage module 507 has the samestructure as the corresponding component of the 3D printing device shownin FIG. 1 or FIG. 2. When the third temperature measurement signalindicates that the temperature of the melt in the storage chamber ishigher than the third desired temperature range, the control module 505performs reverse operation to stop the heating apparatus in the storagechamber of the temporary storage module 507 for heating the melt orreduce the heating power of the heating apparatus.

In some embodiments, a fourth temperature sensor (not shown FIG. 3) isfurther disposed in a mixing chamber of the mixing module 508, and isconfigured to measure the temperature of a melt in the mixing chamber ofthe mixing module 508 and transmit a fourth temperature measurementsignal to the control module 505. The control module 505 controls thetemperature of the melt in the mixing chamber of the mixing module 508within a fourth desired temperature range according to the fourthtemperature measurement signal. The temperature of the melt in themixing chamber of the mixing module 508 should be slightly higher thanthe melting point of the melt, so as to maintain a melted status of themelt in the mixing chamber. Same as the first desired temperature range,the fourth desired temperature range is related to the structure andcomposition of the product needing to be printed, the type of initialmaterial, and the like. The control module 505 may determine the fourthdesired temperature range according to the product needing to beprinted, or according to a status parameter input by a user on a userinterface.

In some embodiments, when the fourth temperature measurement signalindicates that the temperature of the melt in the mixing chamber islower than the fourth desired temperature range, the control module 505may raise heating power of a mixing chamber heating apparatus (not shownFIG. 3) disposed in the mixing chamber of the mixing module 508 for themelt. The mixing chamber heating apparatus disposed in the mixingchamber of the mixing module 508 has the same structure as thecorresponding component of the 3D printing device shown in FIG. 1 orFIG. 2. When the fourth temperature measurement signal indicates thatthe temperature of the melt in the mixing chamber is higher than thefourth desired temperature range, the control module 505 performsreverse operation to stop the heating apparatus in the mixing chamber ofthe mixing module 508 for heating the melt or reduce the heating powerof the heating apparatus.

As shown in FIG. 3 again, in some embodiments, a first pressure sensor(not shown FIG. 3) communicatively connected to the control module 505is disposed in the printing module 503, and configured to measure thepressure of a melt in the printing module 503 and transmit a firstpressure measurement signal to the control module 505. The controlmodule 505 controls the pressure of the melt in the printing module 503within a first desired pressure range according to the first pressuremeasurement signal. The magnitude of the pressure of the melt extrudedfrom the printing module of the 3D printing device and stability of thepressure directly affect continuity and precision of 3D printing. Sameas the first desired temperature range, the first desired pressure rangeis related to the structure and composition of the product needing to beprinted, the type of initial material, and the like. The control module505 may determine the first desired pressure range according to theproduct needing to be printed, or according to a status parameter inputby a user on a user interface. In some embodiments, the printing module503 has a barrel and a nozzle that is disposed below the barrel, wherethe first pressure sensor is disposed in the barrel of the printingmodule 503 and is configured to test the pressure of a melt in thebarrel. In some other embodiments, the first pressure sensor is disposedin a nozzle of the printing module 503, to precisely measure thepressure of a melt extruded from the nozzle of the printing module. Insome embodiments, the first pressure sensor is a piezoelectric pressuresensor, a diffused silicon pressure sensor, a foil gauge pressuresensor, or the like. In some embodiments, the first pressure sensor is afloat-type level gauge disposed in a barrel, and the liquid level of amelt in the barrel is judged to determine the pressure of the currentmelt in the barrel.

In some embodiments, when the pressure of the melt in the nozzle orbarrel of the printing module 503 indicated by the first pressuremeasurement signal is lower than the first desired pressure range, thecontrol module 505 can raise the pressure of the melt in the nozzle orbarrel of the printing module 503 by using the foregoing pressureregulating apparatus disposed in the 3D printing device 100. When thefirst pressure measurement signal indicates that the first pressuremeasurement signal at the nozzle is higher than the first desiredpressure range, the control module 505 performs reverse operation andcan reduce the pressure of the melt in the nozzle or barrel of theprinting module 503 by using the pressure regulating apparatus disposedin the 3D printing device 100.

As shown in FIG. 3 again, the 3D printing device 300 further includes afeeding module 701, configured to receive an initial material andtransmit the initial material to the melt extrusion module 502. Theinitial material received by the feeding module 701 may be differentfrom the initial material received by the feeding module 501. Forexample, the feeding module 501 receives a first initial material, butthe feeding module 701 receives a second initial material. The meltextrusion module 502 is configured to extrude and heat the first initialmaterial and the second initial material. A first composition detector(not shown in FIG. 3), which is communicatively connected to the controlmodule 505, is disposed at any position of the 3D printing device 300,for example, disposed in the storage chamber of the temporary storagemodule 507, the mixing chamber of the mixing module 508, or the printingmodule 503; or in a connection channel between these modules. The firstcomposition detector is configured to measure composition ratios of thefirst initial material and the second initial material in a melt at anyposition of the 3D printing device 300, and transmit a first compositionmeasurement signal to the control module 505. The first compositionmeasurement signal may be a near-infrared spectrum analyzer as describedpreviously. The control module 505 determines a composition of the meltat any position of the 3D printing device 300 according to the firstcomposition measurement signal, and judges whether the composition iswithin a first desired composition range. The composition of the melt ofthe 3D printing device affects physical and chemical properties of afinal product, such as structural strength and disintegration rate.Using 3D printing of pharmaceuticals as an example, the composition ofthe melt probably affects a release rate of an active ingredient of afinal product. Similar to the foregoing desired temperature ranges, thefirst desired composition range is related to physical and chemicalproperties of the product needing to be printed, requirements for thestrength of the product needing to be printed, the structure andcomposition of the product needing to be printed, the type of initialmaterial, and the like. The control module 505 may determine the firstdesired composition range according to the product needing to beprinted, or according to a status parameter input by a user on a userinterface.

In some embodiments, when the composition ratio indicated by the firstcomposition measurement signal shows that a ratio of the first initialmaterial is slightly high, the control module 505 can reduce thedischarge speed of the first initial material or increase the dischargespeed of the second initial material by controlling hopper dischargecontrol apparatuses that are disposed in the feeding module 501 and thefeeding module 701. Specific structures of the hopper discharge controlapparatuses are the same as the structures of corresponding componentsof the 3D printing device shown in FIG. 1 or FIG. 2. When thecomposition ratio indicated by the first composition measurement signalshows that the ratio of the first initial material is slightly low, thecontrol module 505 performs reverse operation and can increase thedischarge speed of the first initial material or reduce the dischargespeed of the second initial material by controlling the hopper dischargecontrol apparatuses disposed in the feeding module 501 and the feedingmodule 701.

In some embodiments, the 3D printing device 300 further includes afeeding module 601 and a melt extrusion module 602, where the feedingmodule 601 is configured to receive an initial material and transmit theinitial material to the melt extrusion module 602. The initial materialreceived by the feeding module 601 may be different from that receivedby the feeding module 501 and the feeding module 701. In this way, amelt ultimately extruded by the melt extrusion module 502 and thatextruded by the melt extrusion module 602 may be different, for example,a first melt and a second melt respectively. As shown in FIG. 3, thefirst melt and the second melt are guided into the mixing module 508 formixing. A second composition detector (not shown in FIG. 3)communicatively connected to the control module 505 is disposed at anyposition of the 3D printing device 300 behind a discharge outlet of themixing chamber of the mixing module 508. The composition detector isconfigured to measure the first melt and the second melt in a mixed meltthat is extruded from the discharge outlet of the mixing chamber as wellas a ratio of a component included therein, and transmit a secondcomposition measurement signal to the control module 505. The controlmodule 505 determines a composition of a melt from a discharge outlet ofthe processing chamber of the melt extrusion module 502 according to thesecond composition measurement signal, and determines whether thecomposition is within a second desired composition range. Same as thefirst desired composition range, the second desired composition range isrelated to physical and chemical properties of the product needing to beprinted, requirements for the strength of the product needing to beprinted, the structure and composition of the product needing to beprinted, the type of initial material, and the like. The control module505 may determine the second desired composition range according to theproduct needing to be printed, or according to a status parameter inputby a user on a user interface.

In some embodiments, when the composition ratio indicated by the secondcomposition measurement signal shows that a ratio of the first melt or aratio of a particular component included in the first melt is slightlyhigh, the control module 505 can reduce the discharge speed of the firstmelt or increase the discharge speed of the second melt by controllingmelt extrusion discharge control apparatuses that are disposed in themelt extrusion module 502 and the melt extrusion module 602. Specificstructures of the melt discharge control apparatuses are the same as thestructures of corresponding components of the 3D printing device shownin FIG. 1 or FIG. 2. When the composition ratio indicated by the secondcomposition measurement signal shows that the ratio of the first melt orthe ratio of a particular component included in the first melt isslightly low, the control module 505 performs reverse operation, toincrease the discharge speed of the first melt or reduce the dischargespeed of the second initial material by controlling the melt extrusiondischarge control apparatuses that are disposed in the melt extrusionmodule 502 and the melt extrusion module 602.

As shown in FIG. 3, the 3D printing device 300 has a temporary storagemodule 507, where the temporary storage module 507 has a storage chamberthat is configured to store a melt extruded from a discharge outlet ofthe melt extrusion module 502. When a first volume sensor (not shown inFIG. 3) is disposed in the storage chamber of the temporary storagemodule 507, the first volume sensor is configured to measure a remainingvolume of the storage chamber of the temporary storage module 507 andtransmit a first volume measurement signal to the control module 505.The control module 505 determines that the material stored in thestorage chamber is too much or too little according to the first volumemeasurement signal, thereby avoiding cases that may affect the pressureof the melt in the 3D printing device 300, for example, a case in whichan excessive amount of material is stored in the storage chamber. Insome embodiments, the first volume sensor may be a flow meter disposedat a feed inlet of the storage chamber of the temporary storage module507 and a flow meter disposed at a discharge outlet of the storagechamber of the temporary storage module 507, so that the remainingvolume of the storage chamber is determined by respectively calculatingan inbound flow volume and an outbound flow volume. The flow meters eachmay be a differential-pressure, rotor-type, or volumetric flow meter.

When the remaining volume of the storage chamber indicated by the firstvolume measurement signal is too small, the control module 505 canreduce the discharge speed of the corresponding discharge outlet bycontrolling one or more discharge control apparatuses disposed in the 3Dprinting device 300, thereby avoiding a case in which an excessiveamount of material is stored in the storage chamber. The one or moredischarge control apparatuses disposed in the 3D printing device 300include but are not limited to a hopper discharge control apparatus ofthe feeding module 501 and a melt extrusion discharge control apparatusof the melt extrusion module 502. Specific structures of the dischargecontrol apparatuses are the same as the structures of correspondingcomponents of the 3D printing device shown in FIG. 1 or FIG. 2. When theremaining volume of the storage chamber indicated by the first volumemeasurement signal is too large, the control module 505 can increase thedischarge speed of the corresponding discharge outlet by controlling theone or more discharge control apparatuses disposed in the 3D printingdevice 300, thereby improving utilization of the device. FIG. 4illustrates a perspective view of a 3D printing device according toanother embodiment of the present invention. As shown in FIG. 4, aprinting module 703 of a 3D printing device 400 includes a plurality ofnozzles 731, where the plurality of nozzles 731 are distributed in anarray, and lengths of connection paths from each nozzle 731 to thedischarge outlet of the processing chamber, the discharge outlet of themixing chamber or the discharge outlet of the storage chamber are thesame, thereby ensuring that each nozzle has an equal pressure during aprinting process, to satisfy the demand for batch production.Alternatively, the plurality of nozzles may be arranged in anotherlayout manner in which the lengths of the connection paths from eachnozzle to the discharge outlet of the processing chamber, the mixingchamber or the storage chamber are the same, for example, roundarrangement or sector-shaped arrangement. The plurality of nozzles 731of the 3D printing device 400 has a same inner diameter, which is about0.05 mm to 2 mm, and the nozzles may be made of a material such assteel, brass, or aluminum alloy. In some embodiments, the inner diameterof each nozzle of the 3D printing device 400 is preferably 0.3 mm, 0.4mm, or 0.5 mm.

In some embodiments, the printing module 703 is connected through a hose(not indicated in FIG. 4) to the processing chamber, the mixing chamber,or the storage chamber. In some embodiments, all modules of the 3Dprinting device that are connected to each other are connected throughhoses, and the foregoing melt flows, through a hose, from the processingchamber of the melt extrusion module into the storage chamber of thetemporary storage module, the mixing chamber of the mixing module, or anozzle of the printing module. In some embodiments, inner diameters ofthe hoses, through which the modules are connected to each other, are 1mm to 100 mm. In some embodiments, inner diameters of the hoses, throughwhich the modules are connected to each other, are preferably 4 mm.

FIG. 5 illustrates a schematic diagram of arrangement of nozzles of a 3Dprinting device on a printing module according to a particularembodiment of the present invention. As shown in FIG. 5, after beingconnected to a printing module 703, the hoses enter four nozzles 714,where the four nozzles 714 are located on a same circumference andequally distributed. With such a design, a product ultimately formedthrough spraying of a nozzle on the platform module can be arrangedneatly in both a horizontal direction and a vertical direction, tofacilitate a subsequent packaging and cutting process.

As shown in FIG. 4 again, the 3D printing device 400 further includes aplatform module 704. The platform module 704 includes a plurality ofdeposition platforms 741, 742 and 743. The plurality of depositionplatforms are disposed on a platform driving mechanism 745. As shown inthe figure, the plurality of deposition platforms 741, 742 and 743 aredisposed on a crawler-type driving mechanism 746 in a belt connectionmanner. The crawler-type driving mechanism 746 is disposed on ahorizontal driving mechanism 747, and can move horizontally along withthe horizontal driving mechanism 747. The crawler-type driving mechanism746 and the horizontal driving mechanism 747 together form the platformdriving mechanism 745. Driven by a motor, the crawler-type drivingmechanism 746 can drive the deposition platforms 741, 742 and 743 tomove along a Y-axis of a Cartesian coordinate system shown in FIG. 4.The horizontal driving mechanism 747 is a stepper motor, and can drivethe deposition platforms 741, 742 and 743 to move along an X-axis of theCartesian coordinate system shown in FIG. 4. The 3D printing device 400further includes a printing module driving mechanism 735. As shown inFIG. 4, the printing module driving mechanism 735 is a stepper motor,and can drive the nozzle 731 of the printing module 703 shown in FIG. 4to move a Z-axis of the Cartesian coordinate system shown in FIG. 4. Itshould be noted that, structures of the printing module drivingmechanism and the platform driving mechanism may be in any combined formto enable the nozzle 731 to move along the X-axis, the Y-axis and theZ-axis of the Cartesian coordinate system relative to the depositionplatform. For example, in some embodiments, the printing module drivingmechanism drives the nozzle of the printing module to move along theX-axis, the Y-axis and the Z-axis of the Cartesian coordinate system,while the platform module 704 keeps still during a product printingprocess. It may be understood that, although the printing module drivingmechanism 735 and the horizontal driving mechanism 747 shown in FIG. 4are stepper motors, they may alternatively be other transmissionmechanisms, for example, hydraulic piston cylinders.

The 3D printing device 400 may further include a product collectionmodule (not shown in FIG. 4). The product collection module isconfigured to collect final products formed on the deposition platforms741, 742, and 743. In some embodiments, the product collection modulemay be a scraper or manipulator, configured to convey the final productsformed on the deposition platforms 741, 742, and 743 to a designatedplatform or a conveyor belt for packaging. In some embodiments, theproduct collection module has packaging, laying, and heat sealingfunctions: A lower layer of package is laid in advance on the platformmodule, and a product is directly printed on the package; and after theproduct is ultimately printed, the product collection module directlycovers a final product with an upper layer of package, and thenpressurization and thermoplastic sealing are performed to finishpackaging, where the package may be aluminum foil, plastic membrane, orthe like.

In some embodiments, the 3D printing device 400 further has an automaticconveyance mechanism (not shown in FIG. 4), where the automaticconveyance mechanism is directly connected to a feed inlet of a feedingmodule, and conveys an initial material to the feed inlet. In someembodiments, the automatic conveyance mechanism may be a belt conveyor,a buried scraper conveyer, a vibration conveyor, a screw conveyor, orthe like. In some embodiments, the automatic conveyance mechanism mayalternatively be equipped with a piezoelectric sensor, configured tomeasure weight of the conveyed initial material and control quantitativeconveying of the initial material according to a measurement result. Thecontrol module of the 3D printing device 400 may control thetransmission speed of various initial materials according to a statusparameter of the device or an instruction input by a user on a userinterface, thereby improving production efficiency.

In some embodiments, the 3D printing device 400 further includes aninspection module (not shown in FIG. 4), where the inspection module isconfigured to measure a product parameter of the final products formedon the platform module. As described previously, a product parameter ofa final product include but are not limited to: a quantity of products,a required composition of the product, required weight of the product,required moisture of the product, and a required quantity of bacteriacolonies of the product. The inspection module is communicativelyconnected to the control module, and transmits the measured productparameter to the control module. The control module determines whetherthe product parameter satisfies an ultimate product requirementaccording to a predefined product requirement or according to aninstruction input by a user on a user interface, determines whether theproduct is qualified according to a determining result, and takes acorresponding measure to correct unqualified device operation.

In some embodiments, the inspection module may include a near-infraredspectrum analyzer as described previously to measure whether acomposition of the final product is qualified. The inspection module mayfurther include a camera, so as to shoot the final product or performoptical inspection on the final product, and make a comparison withstandard requirements through the control module, thereby measuringwhether a size and a shape of the final product formed on the depositionplatforms 741, 742, and 743 conforms to a standard. As describedpreviously, the near-infrared spectrum analyzer may alternatively beused as a moisture sensor. The inspection module may further include apiezoelectric sensor, to measure the weight of the final products. Themeasured product parameter can be conveyed to the control module, andthe control module can automatically regulate the operation of the 3Dprinting device 400 based on the parameter. For details about a specificregulating manner, refer to the aforesaid regulating apparatusescorresponding to the apparatuses for measuring the status parameter ofthe control module and various modules that are disposed in the 3Dprinting device 400, including but not limited to the heatingapparatuses and the discharge control apparatuses.

In some embodiments, the 3D printing device 400 further includes anautomatic screening module, where the automatic screening module isconfigured to pick a final product formed on the deposition platforms741, 742, and 743. In some embodiments, the automatic screening modulehas a high-precision weighing sensor, such as a piezoelectric sensor,which conveys, based on the weight of products ultimately formed on theautomatic screening module, the products to different positions, forexample, conveys a product that does not comply with a weightrequirement to a position in which scrapped products are placed.

In another aspect of the present invention, a 3D printing method isprovided. The 3D printing method includes: melting and pressurizing amaterial; making the material flow through an extrusion port of anozzle, where the nozzle includes a tapered inner surface; monitoringthe pressure of the material in the nozzle or close to the nozzle;making a tapered end of a sealing needle engage with the tapered innersurface of the nozzle, to seal the extrusion port and inhibit flowing ofthe melted material; and withdrawing the tapered end of the sealingneedle, to resume flowing of the material through the extrusion port. Insome embodiments, the method is performed by using the device accordingto the present invention. In some embodiments, the device includes aplurality of barrels, where each barrel is equipped with a controlswitch. The method may include: dispensing a first material from a firstbarrel and dispensing a second material from a second barrel, where asealing needle of the first barrel is in a closed position when thesecond material is dispensed from the second barrel, and a sealingneedle of the second material supply system is in a closed position whenthe first material is dispensed from the first barrel. In someembodiments, the method is performed in batches for processing. In someembodiments, the device or system is controlled to work in batches. Theterm “in batches” refers to a mode of operation in which a predeterminedquantity of products (such as pharmaceutical dosage forms) aremanufactured. In some embodiments, the method is performed in acontinuous mode of operation. In some embodiments, the device or systemworks in a continuous mode. The term “continuous mode” refers to a modeof operation in which the device or system works for a predeterminedperiod of time or until a predetermined amount of a single type ormultiple types of materials have been used.

In some embodiments, the 3D printing method includes: melting andpressurizing a first material; making the first material flow through afirst extrusion port of a first nozzle that includes a tapered innersurface; making a tapered end of a first sealing needle engage with thetapered inner surface of the first nozzle, to seal the first extrusionport and inhibit flowing of the melted first material; melting andpressurizing a second material; and withdrawing a tapered end of asecond sealing needle from a tapered inner surface of a second nozzle,so that the second material flows through a second extrusion port. Insome embodiments, the method includes: receiving an instruction formanufacturing a product, for example, from a computer system.

In some embodiments, a method for manufacturing a pharmaceutical dosageform (such as a tablet) by using the 3D printing method includes thefollowing steps: melting and pressuring a pharmaceutical material;monitoring the pressure of a material within a nozzle or close to thenozzle; making the material flow through an extrusion port of the nozzlethat includes a tapered inner surface; making a tapered end of a sealingneedle engage with the tapered inner surface of the nozzle, to seal theextrusion port and inhibit flowing of the melted material; andwithdrawing the tapered end of the sealing needle, to resume flowing ofthe material through the extrusion port. In some embodiments, thepharmaceutical material includes a drug. In some embodiments, the methodis performed by using the device according to the present invention. Insome embodiments, the device includes a plurality of barrels, where eachbarrel is equipped with a control switch. The method may include:dispensing a first material from a first barrel and dispensing a secondmaterial from a second barrel, where a sealing needle of the firstbarrel is in a closed position when the second material is dispensedfrom the second barrel, and a sealing needle of the second feedingmodule is in a closed position when the first material is dispensed fromthe first barrel. In some embodiments, the method further includes:monitoring the pressure of a first material within a first nozzle orclose to the first nozzle; or monitoring the pressure of a secondmaterial within a second nozzle or close to the second nozzle.

In some embodiments, a method for manufacturing a pharmaceutical dosageform by using the 3D printing method includes: melting and pressurizinga first pharmaceutical material; making the first pharmaceuticalmaterial flow through a first extrusion port of a first nozzle thatincludes a tapered inner surface; making a tapered end of a firstsealing needle engage with the tapered inner surface of the firstnozzle, to seal the first extrusion port and inhibit flowing of themelted first material; melting and pressurizing a second pharmaceuticalmaterial; and withdrawing a tapered end of a second sealing needle froma tapered inner surface of a second nozzle, so that the secondpharmaceutical material flows through a second extrusion port. In someembodiments, the first pharmaceutical material or the secondpharmaceutical material is an erodible material. In some embodiments,the first pharmaceutical material or the second pharmaceutical materialincludes a drug. In some embodiments, the method further includes:receiving an instruction for manufacturing the pharmaceutical dosageform, for example, from a computer system. In some embodiments, themethod further includes: monitoring the pressure of the first materialwithin the first nozzle or close to the first nozzle; or monitoring thepressure of the second material within the second nozzle or close to thesecond nozzle.

FIG. 6 illustrates a schematic diagram of a 3D printing device accordingto another embodiment of the present invention.

FIG. 7A and FIG. 7B each illustrate a model of a pharmaceutical productthat can be printed by using a 3D printing device according to aparticular embodiment of the present invention.

The following describes application of the 3D printing device accordingto the present invention in the field of 3D printing of pharmaceuticalswith reference to FIG. 6, FIG. 7A, and FIG. 7B. It may be understoodthat, the following description is merely an example, and certainly the3D printing device in the foregoing description is applicable toprinting of any other articles that may be obtained through the 3Dprinting device, for example, artificial skeletons, molds, food, andindustrial designs.

As shown in FIG. 6, a 3D printing device 600 includes a plurality ofmelt extrusion modules 961, 962, 963, 964, 965 and 966, and a pluralityof nozzles 951, 952, 953, 954, 955, and 956. For details aboutstructures and function arrangement of the plurality of melt extrusionmodules and the plurality of nozzles, refer to the melt extrusionmodules and nozzles shown in FIG. 1 and FIG. 2. The 3D printing device600 further includes a plurality of deposition platforms 941, 942, 943,944, 945, and 946. For details about structures and function arrangementof the plurality of deposition platforms, refer to the depositionplatforms shown in FIG. 1 and FIG. 2. Melts extruded through theplurality of melt extrusion modules of the 3D printing device 600 aredeposited on the plurality of deposition platforms. The depositionplatforms 941, 942, 943, 944, 945, and 946 can be driven to pass theplurality of nozzles 951, 952, 953, 954, 955, and 956 to receive themelts, and cyclically operate relative to the plurality of nozzles onthe whole. In some embodiments, the plurality of deposition platformsmay perform reciprocating motion between one or more of the plurality ofnozzles, and a detailed description thereof is given later withreference to FIG. 7A and FIG. 7B.

It should be noted that, the 3D printing device 600 shown in FIG. 6includes a plurality of nozzles 951, 952, 953, 954, 955, and 956, wherethe nozzles 951, 952, 953, 954, 955, and 956 may be a single nozzleinstead, or may be a combination of a plurality of nozzles arranged in acertain manner. In some embodiments, the 3D printing device 600 may havea plurality of printing modules respectively corresponding to theplurality of nozzles 951, 952, 953, 954, 955, and 956. In addition,although not shown in FIG. 6, one or more mixing modules or temporarystorage modules may be further disposed between the melt extrusionmodules 961, 962, 963, 964, 965 and 966, and the plurality of nozzles951, 952, 953, 954, 955, and 956 of the 3D printing device 600 shown inFIG. 6. For details about the structure and arrangement of the mixingmodule(s) or the temporary storage module(s), refer to FIG. 1 and FIG.2.

FIG. 7A illustrates a model of a drug 990 that can be printed by using a3D printing device according to a particular embodiment of the presentinvention. The drug 990 includes a drug shell 992 and a drug kernel 993.The shell 992 may be a capsule made of an enterosoluble or gastricsoluble material. The kernel 993 is an active ingredient of the drug.FIG. 7B illustrates a model of a drug 991 that can be printed by using a3D printing device according to a particular embodiment of the presentinvention. The drug 991 includes drug shells 994 and 995, and drugkernels 996 and 997. The shells 994 and 995 may be capsules made ofenterosoluble or gastric soluble materials with different dissolutionand release properties. The kernels 996 and 997 may be different activeingredients of the drug.

In a process of printing the foregoing drug, a control module firstreads a digital drug model shown in FIG. 7A or FIG. 7B, a statusparameter of the drug such as a composition, moisture, and weight, andrequirements on a parameter of a final product. Then the control modulecontrols an automatic conveyance mechanism as described previously tofeed a melt extrusion module through a feeding module. Using the drugmodel shown in FIG. 7A as an example, the melt extrusion module 961receives an initial material that is an enterosoluble material, andextrudes and heats the initial material, so that the initial material isconverted into a melt and the melt is extruded through the nozzle 951.The melt extrusion module 962 is configured to receive an initialmaterial of the active ingredient of the drug, and extrude and heat theinitial material, so that the initial material is converted into a meltand the melt is extruded through the nozzle 952. A platform drivingmechanism drives the deposition platform 941 to first move to a positionbelow the nozzle 951, so that a lower half concave part of the drugshell 992 is ultimately formed by stratified deposition on thedeposition platform 941 through relative motion between the nozzle 951and the deposition platform 941. Then the platform driving mechanismdrives the deposition platform 941 to move to a position below thenozzle 952, and the drug kernel 993 is ultimately formed in the lowerhalf concave part of the drug shell 992 by stratified deposition on thedeposition platform 941 through relative motion between the nozzle 952and the deposition platform 941. Then the deposition platform 941 isdriven to return to a position below the nozzle 951, so that an upperhalf part of the drug shell 992 is ultimately formed by stratifieddeposition on the deposition platform 941 through relative motionbetween the nozzle 951 and the deposition platform 941, therebyultimately forming the drug model shown in FIG. 7A. In some embodiments,the melt extrusion module 963 shown in FIG. 6 may have a same initialmaterial as the melt extrusion module 961, and extrudes and heats theinitial material, so that the initial material is converted into a meltand the melt is extruded through the nozzle 953. Therefore, afterprinting the drug kernel 993, the deposition platform 941 can move to aposition below the nozzle 953, to finish printing of the drug modelshown in FIG. 7A. It may be understood that, the plurality of depositionplatforms 941, 942, 943, 944, 945, and 946 may pass below the nozzles951, 952, and 953 in turn, to finish printing of the drug model shown inFIG. 7A in a pipeline manner, thereby effectively improving drugprinting efficiency and satisfying a mass production requirement.Certainly, in some embodiments, the deposition platform 941 mayalternatively perform reciprocating motion between the nozzle 951 andthe nozzle 952, to finish printing of the drug model shown in FIG. 7A.Similarly, the deposition platform 942 may perform reciprocating motionbetween the nozzle 952 and the nozzle 953, to finish printing of thedrug model shown in FIG. 7A.

It should be noted that, in some embodiments, stratified printing may bestrictly performed for the drug model shown in FIG. 7A. The 3D printingdevice 600 may stratify the drug model shown in FIG. 7A from top tobottom, and drive the deposition platform 941, through the platformdriving mechanism, to first move to a position below the nozzle 951, sothat a single stratified portion including only the drug shell 992 isultimately formed by stratified deposition on the deposition platform941 through relative motion between the nozzle 951 and the depositionplatform 941. When printing a single stratum including both the drugshell 992 and the drug kernel 993, the 3D printing device 600 drives,through the platform driving mechanism, the deposition platform 941 toperform reciprocating motion between a position below the nozzle 951 anda position below the nozzle 952, so that the single stratum includingboth the drug shell 992 and the drug kernel 993 is ultimately formed bystratified deposition on the deposition platform 941 through relativemotion between the nozzles and the deposition platform 941.

A printing manner for the drug model shown in FIG. 7B is similar to thatshown in FIG. 7A. First, a lower half concave part of the drug shells994 and 995 may be dispensed, then a drug kernel part of the kernels 996and 997 is dispensed, and finally an upper half part of the drug shells994 and 995 is dispensed. In some embodiments, alternatively the drugmodel shown in FIG. 7B may be stratified first, to strictly performstratified printing. In some embodiments, a drug model including aplurality of different components may be printed by using a plurality ofdifferent melt extrusion modules and/or printing modules. As shown inFIG. 7B, the drug model 994 may be made of an enterosoluble material,the kernel 997 is an active ingredient that needs to be released in anintestine, the drug model 995 is made of a gastric soluble material, andthe kernel 996 is an active ingredient that needs to be released in astomach. Therefore, the drug model shown in FIG. 7B enables release withdifferent efficiency in different organs, and pharmaceutical productswith various special structures and requirements shown in FIG. 7B can beefficiently and quickly printed in batches by using the 3D printingdevice disclosed herein.

The 3D printing device disclosed herein also meets a continuousmanufacturing of pharmaceuticals (CMP) requirement. With the foregoingcontrol module, inspection module, and status parameter measurementapparatuses, the 3D printing device can monitor, in real time, a productparameter or a status parameter of a final product or an intermediateproduct of a drug needing to be printed, such as a composition,moisture, weight, and shape; and can regulate a product parameter or thestatus parameter through components such as the foregoing dischargecontrol apparatuses and heating apparatuses, thereby avoiding numerousproblems brought by batch production of pharmaceuticals and improvingproduction efficiency.

FIG. 8 illustrates a flowchart of a 3D printing method according to aparticular embodiment of the present invention.

The present invention further discloses a 3D printing method for productprinting by using the 3D printing device disclosed herein. The followingdescribes in detail the 3D printing method with reference to FIG. 1,FIG. 2, and FIG. 3. For details about implementation of specificfunctions in specific steps of the method, refer to the arrangement ofspecific components and functions in the foregoing 3D printing deviceembodiments of the present invention. The 3D printing method includes:feeding a first initial material to a processing chamber 121 of a meltextrusion module 102 of a 3D printing device 100; heating and extrudingthe first initial material in the processing chamber 121, so that thefirst initial material is converted into a first melt and the first meltis extruded from a discharge outlet 125 of the processing chamber 121;and guiding the first melt at the discharge outlet 125 of the processingchamber 121 to be extruded through a nozzle 131 of the printing module103 and deposited on a platform module 104.

In some embodiments, the 3D printing method further includes: feedingthe first initial material to the melt extrusion module 102 through ahopper of a feeding module 101.

In some embodiments, the 3D printing method further includes: measuringthe pressure of the first melt in the printing module 103; andcontrolling the pressure of the first melt in the printing module 103according to the measured pressure.

In some embodiments of the present invention, the 3D printing methodfurther includes: measuring the temperature of the first hybrid melt inthe printing module 103; and regulating the temperature of the firstmelt in the printing module 103 according to the measured temperature.

In some embodiments, the 3D printing method further includes: measuringthe temperature of the first melt in the processing chamber 121; andcontrolling heating power and/or extrusion power for the first melt inthe processing chamber 121 according to the measured temperature.

In some embodiments, the step of guiding the first melt at the dischargeoutlet of the processing chamber 121 to be extruded through the nozzle131 of the printing module 103 and deposited on the platform module 104specifically includes: guiding the first melt at the discharge outlet125 of the processing chamber 121 to enter a storage chamber 171 of atemporary storage module 107; and guiding the first melt at a dischargeoutlet of the storage chamber 171 to be extruded through the nozzle 131of the printing module 103 and deposited on the platform module 104.

In some embodiments, the 3D printing method further includes: measuringthe temperature of the first melt in the storage chamber 171; andcontrolling heating power for the first melt in the storage chamber 171according to the measured temperature.

In some embodiments, the 3D printing method further includes: measuringa remaining volume of the storage chamber 171; and controlling thedischarge speed of the first melt at the discharge outlet 125 of theprocessing chamber 121 according to the remaining volume of the storagechamber 171.

In some embodiments, the 3D printing method further includes: guiding atleast a part of the first melt extruded from the discharge outlet 125 ofthe processing chamber 121 to flow back to the processing chamber 121.

As shown in FIG. 2, in some embodiments, the 3D printing method furtherincludes: feeding a second initial material to a processing chamber of asecond melt extrusion module 402 through a hopper of a second feedingmodule 401; heating and extruding the second initial material in theprocessing chamber of the second melt extrusion module 402, so that thesecond initial material is converted into a second melt and the secondmelt is extruded from a discharge outlet of the processing chamber ofthe second melt extrusion module; mixing the first melt and the secondmelt in a mixing chamber 308, to form a first mixed melt; and guidingthe first mixed melt at a discharge outlet of the mixing chamber 308 tobe extruded through a nozzle 331 of a printing module 303 and depositedon a platform module 304.

In some embodiments, the 3D printing method further includes: measuringa composition of the first mixed melt extruded from the discharge outletof the mixing chamber 308; and controlling the discharge speed of thefirst melt at a discharge outlet of a processing chamber of a first meltextrusion module 302 and the discharge speed of the second melt at thedischarge outlet of the processing chamber of the second melt extrusionmodule 402 respectively according to the measured composition of thefirst mixed melt.

In some embodiments, the 3D printing method further includes: measuringthe temperature of the first mixed melt in the mixing chamber 308; andcontrolling heating power for the first mixed melt in the mixing chamber308 according to the measured temperature.

As shown in FIG. 1, in some embodiments, the 3D printing method furtherincludes: feeding a second initial material to the processing chamber121 of the first melt extrusion module 102 through a hopper 211 of asecond feeding module 201; and heating and extruding the first initialmaterial and the second initial material in the processing chamber 121,so that they are converted into a first melt.

In some embodiments, the 3D printing method further includes: measuringa composition of the first melt at any position of the 3D printingdevice 100, and controlling the discharge speed of the first initialmaterial at a discharge outlet of the first feeding module 101 and thedischarge speed of the second initial material at a discharge outlet ofthe second feeding module 102 respectively according to the measuredcomposition of the first melt.

As shown in FIG. 6, in some embodiments, the 3D printing method furtherincludes: feeding a second initial material to a processing chamber of asecond melt extrusion module 962 through a hopper of a second feedingmodule (not shown in FIG. 6); and heating and extruding the secondinitial material in the processing chamber of the second melt extrusionmodule 962, so that the second initial material is converted into asecond melt and the second melt is extruded from a discharge outlet ofthe processing chamber of the second melt extrusion module 962; guidingthe second melt at the discharge outlet of the processing chamber of thesecond melt extrusion module 962 to be extruded through a second nozzle952 of the printing module and deposited on a platform module 941; anddriving the platform module 941 to move between a position below a firstnozzle 951 and a position below the second nozzle 952.

As shown in FIG. 4, in some embodiments, the 3D printing method furtherincludes: driving a nozzle 731 of the printing module to move relativeto the platform module.

In some embodiments, the 3D printing method further includes: drivingthe nozzle 731 of the printing module to move along a Z-axis shown inFIG. 4 relative to the platform module.

In some embodiments, the 3D printing method further includes: driving afirst deposition platform 741 of the platform module to move relative tothe nozzle 731 of the printing module, where the first depositionplatform 741 is configured to receive the first melt extruded throughthe nozzle 731.

In some embodiments, the 3D printing method further includes: drivingthe deposition platform 741 to move along an X-axis and/or a Y-axisshown in FIG. 4 relative to the nozzle 731.

In some embodiments of the present invention, the 3D printing methodfurther includes: collecting a final product formed on the platformmodule 104.

In some embodiments of the present invention, the 3D printing methodfurther includes: measuring a product parameter of a final productformed on the platform module 104.

In some embodiments of the present invention, the 3D printing methodfurther includes: picking a final product formed on the platform module104.

In some embodiments, the 3D printing method further includes: conveyingthe first initial material to the feeding module 101 through anautomatic conveyance module.

In some embodiments, the 3D printing method may be used for dispensing athermoplastic material, especially in scenarios such as continuousproduction, individualized production, and batch production ofpharmaceuticals.

It should be noted that, although the several modules or sub-modules ofthe 3D printing device are mentioned in detail in the foregoing detaileddescription, such division is merely an example but not mandatory. Infact, features and functions of two or more of the foregoing modulesaccording to the embodiments of the present application may beintegrated into one module during specific implementation. On thecontrary, features and functions of one module in the foregoing modulesmay be further divided into a plurality of modules during specificimplementation.

Persons of ordinary skill in the art may understand and implement othervariations to the disclosed embodiments by studying this specification,the disclosed content, the accompanying drawings, and the appendedclaims. In the claims, the term “comprising” does not exclude otherelements and steps, and the terms “one” and “a” do not excludeplurality. During practical application of the present application, onespare part may perform functions that integrate a plurality of technicalfeatures quoted in the claims. The accompanying drawing reference signsshall not be construed as limiting the scope of the present invention.

The foregoing is an exemplary description of various embodiments of thepresent application with reference to the accompanying drawings. Personsskilled in the art may be easily aware that, in combination with thecontent disclosed in this specification, various components of the 3Dprinting device disclosed in various embodiments may be appropriatelyregulated or recombined according to actual needs, without departingfrom the spirit of the present invention. The protection scope of thepresent application shall be subject to the protection scope of theclaims.

The invention claimed is:
 1. A 3D printing method of making a pharmaceutical tablet, comprising: feeding a first initial material and a second initial material different from the first initial material to a processing chamber of a first melt extrusion module according to a desired composition range of the pharmaceutical tablet calculated based on a predefined release rate of an active ingredient of the pharmaceutical tablet, wherein at least one of the first initial material and the second initial material comprises the active ingredient; simultaneously heating and mixing the first initial material and the second initial material in the processing chamber of the first melt extrusion module to convert the mixed first initial material and the second initial material into a first melt in a melted form at a first temperature higher than the melting point of the active ingredient of the pharmaceutical tablet; while ensuring that the first melt is in the melted form at a second temperature determined based on the melting point of the active ingredient, conveying the first melt from a discharge outlet of the processing chamber of the first melt extrusion module to a feed inlet of a first printing module, wherein the first printing module is separate from the processing chamber of the first melt extrusion module; and while ensuring that the first melt is in the melted form at a third temperature determined based on the melting point of the active ingredient, controlling the first melt to be extruded through a first nozzle of the first printing module and deposited on a platform module to make the pharmaceutical tablet comprising the active ingredient.
 2. The 3D printing method of claim 1, further comprising: feeding the first initial material to a first inlet of the processing chamber of the first melt extrusion module at a first discharge speed; feeding the second initial material to the first inlet of the processing chamber of the first melt extrusion module at a second discharge speed, wherein the first discharge speed and the second discharge speed is set according to the desired composition range of the pharmaceutical tablet.
 3. The 3D printing method of claim 1, further comprising: measuring the pressure of the first melt in the first nozzle; and controlling a pressure regulating apparatus based on the measured pressure to maintain the pressure of the first melt in the first nozzle to be an approximately constant pressure.
 4. The 3D printing method of claim 1, further comprising: measuring the temperature of the first melt in the first nozzle; and regulating based on the measured temperature, the temperature of the first melt in the first nozzle to be an approximately constant temperature.
 5. The 3D printing method of claim 2, further comprising: feeding a third initial material to a processing chamber of a second melt extrusion module through a hopper of a second feeding module; heating and extruding the third initial material in the processing chamber of the second melt extrusion module, so that the third initial pharmaceutical material is converted into a second melt and the second melt is extruded from the discharge outlet of the processing chamber of the second melt extrusion module; guiding the second melt at the discharge outlet of the processing chamber of the second melt extrusion module to be extruded through a second nozzle of the first printing module and deposited on the platform module; and driving the platform module to move between a position below the first nozzle and a position below the second nozzle.
 6. The 3D printing method of claim 5, further comprising: driving a first deposition platform of the platform module to move relative to the first nozzle of the first printing module; and driving a second deposition platform of the platform module to move relative to the first nozzle of the first printing module; wherein the first deposition platform and the second deposition platform are both configured to receive the first melt extruded through the first nozzle; and wherein the first deposition platform and the second deposition platform pass below the first nozzle in turn.
 7. The 3D printing method of claim 1, further comprising one or more of the following: i) collecting a final product of the pharmaceutical tablet formed on the platform module; ii) measuring a product parameter of a final product of the pharmaceutical tablet formed on the platform module; and iii) picking a final product of the pharmaceutical tablet formed on the platform module.
 8. The 3D printing method of claim 1, further comprising: measuring a composition ratio of the first initial material and the second initial material in the first melt in the processing chamber of the first melt extrusion module; reducing a first discharge speed of the first initial material or increasing a second discharge speed of the second initial material if the composition ratio indicates that the ratio of the first initial material is higher than the desired composition range of the pharmaceutical tablet; increasing the first discharge speed or reducing the second discharge speed when the composition ratio indicates that the ratio of the first initial material is lower than the desired composition range.
 9. The 3D printing method of claim 1, further comprising: controlling the first melt in the first nozzle to be heated to a higher temperature than in the first melt extrusion module.
 10. The 3D printing method of claim 1, wherein the third temperature is higher than the second temperature.
 11. The 3D printing method of claim 1, wherein ensuring that the first melt is in the melted form at the second temperature comprises: obtaining an output from one or more sensors in a feed channel; and controlling a heater based on the output from the one or more sensors in the feed channel.
 12. The 3D printing method of claim 1, wherein ensuring that the first melt is in the melted form at the third temperature comprises: obtaining an output from one or more sensors in a printing head; and controlling a heater based on the output from the one or more sensors in the printing head. 